Which mobile OS is the most stable for installed apps?

1. I was tasked to research a comparison of mobile operating systems that is the least problematic, most stable, no crash, when installing and running the same app version in Android and iOS, considering that the app uses an embedded database.

2. Do the same app behave differently especially when used in a tablet vs cell phone?

3. Which OS gives the user the best experience when using the app?

Many of you might have been developing database app for both OS for your clients and I have no experience in this, yet. 🙂

Thank you for any input you may have on my inquiry.