I think there are two very different things you want. One is test our application on a great number of devices and Android version combinations. This is to make sure your app runs smoothly on all the environments you need. The other is a way to collect usage data, core dumps and physicians feedback.

The first thing can be accomplished with a device farm and automated tests. Xamarin Test Cloud ( http://xamarin.com/test-cloud ) allows you to to automated testing on about 600 devices. There are other providers but this is the one that I would use and trust the provider.

The second thing can be accomplished using many tools, even the ones you already use, e.g., trello or slack, for feedbacks. I have seen many companies go for beta releases on Google Play linked with private Google+ groups for beta testers.

For crash dumps and usage monitoring you can use Twitter Clashalytics ( http://try.crashlytics.com/ ) or other tools like:

* http://www.mobtest.com/
* http://ubertesters.com/
* http://hockeyapp.net/
* http://www.centercode.com/

I have worked with several internet healthcare startups. What type of app is it? What does it do? And the best answer is....always test, test, test.
Best of Luck,
Michael T. Irvin
michaelirvin.net
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