Rodrigo Neri

iOS & Web Developer + Designer + Entrepreneur Co-Founder of Instin

Version 2: Turn a light bulb ON with every new user or download (using Philips Hue)

Posted 1 year ago

About 4 months ago I wrote a blog post about something I had hacked together that turned a light bulb on every time we had a new user or download. The project was a DIY kind of project where I had gone to Home Depot bought a few materials and was able to control 2 light bulbs using a USB cable. 

The project was received quite well, it got several comments and votes on Hacker News. Some of the comments were about how to achieve the same goal but using different boards, switches or light bulbs. One of the comments was about using the Philips Hue light bulb which I thought it was a good idea.

About a week later I met Ben Milne (Founder and CEO of Dwolla) during Big Omaha, Ben was originally the one that gave me the idea about the project. So while talking to him I decided to give him the project with the goal of eventually making a second version of it.

4 months later; The number downloads of our app started to pick up due to being back to school time, and I started to wonder how the light bulbs would look like if I still had them. So this past weekend I decided to work on the second version of that project, I went to the Apple Store and bought the Philips Hue 3 bulb starter pack.


The starter pack comes with 3 LED based light bulbs and a bridge. The bridge connects to your local network and it’s what is used to control the bulbs. I was extremely impressed how easy it was to get it working, 3 easy steps printed on the box and that’s all it takes for you to control those light bulbs using your iPhone. 

After I got done playing with those lights I started to look into ways I could control them using code. So I looked through the Philips Hue API documentation and once again I was impressed how easy it was to get it to work, turns out that the bridge you connect to your local network has it’s own little web server that you can directly call the APIs. So all I had to do is update the code I had written 4 months ago to instead of controlling the USB port to just send a message to the bridge to control a light bulb.

Here’s a video of it working. Every time a student creates a myHomework account the top light turns ON, and every time a student downloads the myHomework app (between the different platforms) the bottom light turns ON.

Every new user or download counts for 1 second, so sometimes you will see the downloads light on for a little while that means that there’s a new download for every second that’s on. If you compare it with the video I posted 4 months ago I was fetching data every 30 seconds, that’s because we weren’t getting as much downloads since students were almost out of school. But since it’s Back to School time, the video above is fetching for new data every 2 seconds, so it’s almost real time :)

So I decided to play around a bit and use the color functionality of the Philips Hue, so on the video below instead of turning the light on and off the light turns blue instead. Don’t think it’s as cool, what do you think?

Overall I’m really impressed by the Philips Hue, the only thing I didn’t like is the price but I can already see other ways I can put those light bulbs to use. If you are interested in the source code I used just send me an email and I would be more than happy to share.

Turn a light bulb ON with every new user or download

Posted 1 year ago

About a year ago, maybe two I saw a tweet from Ben Milne, CEO of Dwolla that went along these lines: “I once wanted to light a light bulb every time we had a new transaction, today that light bulb would be on all the time” At the time I thought it was a really cool idea and wanted to do something similar, but the idea just got locked up in my head and I end up not doing anything about it.

A few weeks ago I met Ben at Big Kansas City and we talked about that idea, he said he did end up working on it at one point but the only thing left to finish was actually going out and buying the light bulb.

The next day I couldn’t stop thinking about it. It would be really cool if every time we had a new myHomework user or a new download a light bulb would light up. So I went around the internet trying to figure out if there was a way to control a lightbulb via USB. I end up finding this instructable that shows a step by step guide of how to control AC devices with your computer. So I decided to build it.

In the video every second counts as 1 new user or 1 new download. Every 30 seconds the program calls our private stats api and if there is a new user or download it turns the light bulb on.

To build it you need a USB Relay Interface called U451 made by that you can only order via internet via Even though their websites look like it was made in the 90’s I was able to order it and have the U451 delivered after a few days.

The instructable does a good job explaining what you need to do step by step. The problems were that it was hard to get the exact same materials and the the programing they show in the end was to be run in some Windows 95 computer. So I had to improvise:

UPDATE: Please be very CAREFUL when hacking on AC devices. 110V current is extremely dangerous and can potentially kill. Read carefully the instructions and do never touch the U451 when it’s turned on. Use the blue shallow box to cover it up (with screws) before turning on. 



Here is the full list of materials that I used, I was able to get them all at Home Depot:

Also make sure to have some wire crampers & strippers and a tiny screwdriver (the smallest you can find, to open close the relay terminals).


So since I couldn’t use their programming instructions to control the light bulb I had to figure something else out. I first tried using Python (pyusb) but  the problem I was running into was getting full access to control the USB port, even trying as root I couldn’t get access.

So while troubleshooting I found a USBMicro library using C & Objective-C, since I’m pretty familiar with those I decided to just use it and went smoothly from there. 

I end up creating a project called Light-U451 and put it on GitHub. The project allows you to control the lights with the push of a button on the screen, you can use this as a base for your own project. All I did differently from this project was call a private api that returns the count of new users and downloads and turn the light on every time I get something new. 


It’s really awesome to visualize the number of users and downloads you get during the day with a light turning on. Usually those are just numbers you see on your analytics tool and after some time doesn’t mean much, just a number. But with a light turning on it makes that action alive! Sometimes you forget that there are actual people out there trying and using your products, when you see that light turn on it reminds you that you are actually touching people lives and not just making software.

We’ve been bootstrapping Instin (myHomework and for about a year now (a post about that to come), we don’t have an office, we usually work from our homes, so when that light turns on it’s just me seeing it. So when we do have an office I will want this to be where everyone in the team can see it, so when they do they can feel the same way as I do. Having these light bulbs introduced me to a new goal of having that light on at all times.


Ryan, my co-founder gave the idea that I should get a red light bulb and if there is ever 500 error in the server or the servers are down that red light should turn on.


If you like it give it a up on Hacker News :)


SoSummit 2013 & Big Kansas City

Posted 1 year ago

It’s been a few months since I wrote my last post and a lot happened since then. In this post I’ll highlight 2 events that I attended during that time, so here it go:


SoSummit 2013

Last month I attended the Startup Weekend Organizers Summit which was held in Rio de Janeiro, Brazil! I’ve been organizing Startup Weekends in Kansas City for about a year now and I was fortunate to have the opportunity to go for free! 

It was an awesome experience meeting SW organizers from all over the world where most of them share similar goals as me, such as making better startup communities where we live. It was really cool to see how different some startup weekends are specially overseas. For example in Morocco they sell out startup weekends over night for 1000 people, compared to KC where we cap at 100 and some events we don’t sell out. After talking with some of the organizers came to find out that the event is free because of the amount of sponsors they have. 



Another cool part of the summit were the speakers, who are somewhat well known in the startup world! 

Overall the summit was great. I was able to meet some really cool people from all over the world, most that offered a place to crash if I ever go by where they live. I hope I get to go again next year, I’m sure it will definitely be worth it.


Big Kansas City

The week after I came back from SOSummit I volunteered at Big Kansas City. Big KC is part of a series of 3 “Big” events in the Silicon Prairie organized by Silicon Prairie News. The other two you probably seen me write about it: Big Omaha and Big Iowa (formally Thinc Iowa). It’s usually a 2 day event where mostly successful entrepreneurs from all over the US come give a talk about some experience they had while inspiring the audience. 

This event was our first Big series event in Kansas City. Some of the big names speaking were: Scott Harrison (Charity Water), Alexis Ohanian (Reddit), Dan Martell (Clarity), Micah Baldwin (, Mike Macadaan (Science) and etc…

Since I was volunteering at the event, my task was to take care of the slides and make sure it was all working. So I was mostly backstage while the event was going. The cool thing about it was that I got to see how nervous some of the speakers get before going on stage and what they do to calm themselves down. Each one does something different, some pace back and forth, some do some breathing exercises, some go over their deck and some speak to the wall :)

Another cool thing was that as soon as they got off the stage I usually had a question for them which sometimes got them to talk a little further than just the Q&A they give on stage.

One of the cool things about Big events is that the speakers stick around for the parties. This time close to the end of the closing party I got to play Warewolf with some of the speakers. Micah Baldwin was the one that put it together and I’ve heard that he did that when he spoke at Big Omaha a few years ago.

Overall Big KC was just like the other Big Series event: very well organized, an impressive attention to detail, great speakers and great parties. Can’t wait for Big Omaha in a few weeks!


Introducing Clash Tactics

Posted 1 year ago


For the past couple of months I’ve been playing a game on my iPad called Clash of Clans. An addictive iOS only combat strategy game that allows you to build and defend your village while battling with people all over the world. Clash of Clans has become really popular, to the point that it has been the top grossing app in the App Store for several weeks, with millions of downloads.

In order to succeed in this game you need to have a strong defensive village so that when you get attacked you don’t lose a lot of resources needed for upgrades. However there are numerous ways to layout your village based on your level. While playing I found myself going around looking at other villages to get ideas on how to make mine better. That took time and most of the time the village I was looking at wasn’t in the same level as mine.

So I thought to myself “Wouldn’t it be cool if there was an app where players could upload screenshots of their villages and vote up which ones are the best, so it’s easier to find the best layout for your level? Maybe since there are a lot of people playing this game people will use it…” So I decided to build it!

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2012 Year in Review & 2013 goals

Posted 1 year ago

Every year I like to look back at the year that has passed and reflect upon it. This year is no different but I’m a little late. I spent the holidays with my family in Brazil and just now I’m getting back on computer/work mode.  

The year started I was still at Cerner, working 9 to 5 and coming home and working on side projects. My role at Cerner was good, I had been promoted few months back, now reporting to a director being somewhat the lead front-end web dev trying to put in place a standard that could be used among different teams inside our group. 

March came around I went to SXSW for the second time, however this time it wasn’t as great as the year before. There were too many people and the weather didn’t help much since some of the sessions were in different buildings. However every time I go there it seems to be something that ignites the entrepreneur bug that crawls in my blood. When I came back I was pumped about the work I was doing on the side but not about the one that I was doing during the day. Things weren’t the same anymore, our group had gotten even bigger, and instead of working towards building a product I was working on things that other developers would use. I wasn’t happy, I wasn’t passionate about it anymore, and came to find out that Keith and Ryan (my co-founders) weren’t either so we begin to explore other options…

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myHomework’s History & Design Evolution

Posted 1 year ago

We just finished releasing a major update to myHomework where students can now join a class and automatically receive assignments, tests, syllabus, attachments and announcements directly on their devices. Every major release I rethink the design and try to make it look better than before. This time was no different. myHomework has been around for a couple of years now, so I’ve gathered enough assets that I think it’s time to write about its evolution, where it came from, what it means, etc…


It all started with the iPhone app in 2009. I was still in college, the iPhone SDK had come out, people were starting to write apps and become successfull, so I decided to do the same. I thought to myself that even if the app didn’t become successful at least it was a great thing to have on a resume. So I went out to B&N, bought one of the first books dedicated exclusively to Objective-C and started learning. A few days later I started to get the hang of it and started thinking of what kind of app to build. 

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Designing for Windows 8 Metro

Posted 2 years ago

We’ve recently finished building our cross-platform student planner app, myHomework for Windows 8. It will be available for download when the Windows 8 Store launches October 26th. I recommend you reading the blog post my co-founder Ryan put together about us building the app: From Zero to Windows 8 Store in Two Weeks.

Towards the end of the summer we got approached by Microsoft into building myHomework for Windows 8, we were really impressed by their demo so we agreed to do so. After playing around with the OS and some of the pre-built apps we’ve learned that designing a Windows 8 app is a lot different than designing an iPad app or a Website. In this post I want to outline some of the things we learned.


The first thing I noticed when playing with Windows 8 is the clean layout. Everything is composed by tiles that most of the time takes you to a detailed view of an item. These tiles are placed vertically but grouped horizontaly, so unlike an iPad app or a Website were most of the scrolling is vertical, on Windows 8 most of the scrolling is horizontal. For example here is a screenshot of the (all) Homework page of myHomework:


In iOS or Web these homework items would be placed one below the other where you would have to scroll down to see more. In Windows 8 once the tiles reach the bottom of the page the next tile is placed on the column to the right and whenever you need to see more you just scroll to the right.

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Introducing Better Nest: A better home experience

Posted 2 years ago

I’ve tried all kinds of Twitter clients for my Mac and didn’t find one that really satisfied me, so when Twitter created the #NewNewTwitter I decided to stick with the website version. But that still wasn’t enough for me, I wanted to know information such as: who unfollowed me, my past tweets and etc… So since I’m a developer I decided to write some code to enhance the page and some of you might find it useful as well.

I would like to introduce Better Nest a Chrome extension that modifies the current page by giving you features that you really care about.


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We’ve been nominated for the Silicon Prairie Awards!

Posted 2 years ago

We so excited! Silicon Prairie News announced last week that we were nominated for 2 categories on the inaugural 2012 Silicon Prairie Awards! Which are awards given to companies and individuals for their outstanding products, strong leadership and noteworthy contributions to the Silicon Prairie community (Nebraska, Iowa, Missouri and Kansas region). If you are familiar with Techcrunch’s Crunchies Awards, it’s the same thing but for companies and individuals in the Midwest.

I was nominated for Startup Technologist of the Year which description follows:

This team member, freelancer or consultant made a significant contribution toward development of a startup’s product. (Contributed to startup product active between July 1, 2011 - June 30, 2012.)

And our app myHomework was nominated for Mobile App of the Year which description follows:

This app featured a notable design and user interface, broke the mold for what we’d expect from a mobile app or reached a high number of downloads.

So, If you think myHomework and I deserve to get an award, vote for us!! Voting closes August 22nd.

A new swimming sport? Underwater Rings

Posted 2 years ago

Last night I was watching the 2012 Olympics swimming and after some time I noticed how every race was pretty much the same. Each race was one of the 4 different stroke types: freestyle, butterfly, breast stroke and backstroke. The only difference being the distance or a mix between the 4. Now, I know that they try to make these races really exciting (which some are) but after some time I started to get bored, so I started to daydream a little… 

What if there was a new swimming sport? I know that they have other swimming/water sports such as synchronized swimming, water polo, and diving (which btw is really cool to watch)…  But it hasn’t been a new in-water sport since the beginning of the 1900s.

One game I used to play when I was a little kid, and I’m sure other kids did as well, was to see If I could go underwater from one side of the pool to the other. What if this new sport had that rule in it? You would have to be underwater at all times. I know that might be too easy for some of these olympic swimmers, but what if we turned the difficulty up a little?

It would be a time based sport which the fastest win. There would be rings of different sizes at different locations that the swimmer had to go through in order. If the swimmer touched a ring, a penalty time would be added to the swimmers’ time. It could be just like the traditional races with different lengths 50m, 100m, 200m and etc…

I put together some sketches to make it easier to picture the sport:

After some googling I found that in the 1900 Olympics there were both underwater and obstacle races and after that year it never happened again. I wonder why…

I’m not sure how sports used to get started but I feel that some innovation need to happen, we’ve been playing the same sports for a long time, it’s time to change, some of these sports are getting boring and I think it’s a perfect time to try…