Last week Brent Simmons posted a pair of articles talking about dropping support for old OS versions in our apps. I generally agree with everything he said but one point stuck with me that I wasn’t so sure about. One of his bullet points justifying being aggressive with dropping OS support was:
People who don’t upgrade their OS are also the kind of people who don’t buy apps.
This isn’t a new idea. It is something I often hear in developer discussions about our customers. My instinct was to agree with this notion. However, it bothered me a bit that I was making a sweeping generalization without much in the way of substantiation. If you’ve been reading this site for any length of time you know I have a bit of a fixation with using data to answer questions like this.
I got to thinking about if I could answer this question more quantifiably using my app catalog as a sample set. Restating the question a bit led to a hypothesis I could actually validate. Does the population of new purchasers of my apps differ from the general population who uses them? If people who don’t update also purchase fewer apps then I’d expect to see my new user numbers skew dramatically towards newer OSs.
Looking at the data I had available to me I settled on using the data from My Recipe Book as the test case. It is a universal, paid application that supports users running iOS 5.1 or greater. More importantly it uses a custom sync backend for storing user’s recipes. This allows me to identify the OS version of devices creating new user accounts and then comparing them to all sync calls. For the purposes of this analysis I looked at the last 1000 user accounts created.
All Devices
| New Purchases | All Users | |
|---|---|---|
| 5.x | 4% | 4% |
| 6.x | 4% | 6% |
| 7.x | 92% | 90% |
iPad Only
| New Purchases | All Users | |
|---|---|---|
| 5.x | 0% | 0% |
| 6.x | 5% | 6% |
| 7.x | 95% | 94% |
iPhone Only
| New Purchases | All Users | |
|---|---|---|
| 5.x | 8% | 5% |
| 6.x | 3% | 6% |
| 7.x | 89% | 89% |
I was a bit surprised at how straightforwardly this analysis came out. It seems clear that the distribution of people who are purchasing your apps follows closely the overall adoption of users. There doesn’t seem to be anything about their speed of update that impacts their purchasing habits.
Now, that doesn’t mean that dropping support for older versions isn’t a good idea. It just means that this particular line of reasoning shouldn’t be your primary justification. If anything this shows the importance of the dramatic speed at which the general population adopts new OS versions.
You are excluding some paying customers when you drop OS support, but you are dropping a vanishingly small proportion.