I’ve used Lookback in the past and really like it. It works for both iOS and Android. It can record everything that’s happening on a user’s screen, as well as their voice and face. Also, multiple people in your group are able to share and comment on the recording in the Lookback.io interface.
The one downside is that in order to allow participants to use their own iOS devices, you must embed Lookback as an SDK in your app, which is kind of a plugin for your mobile app. It only records your app, and can thus be bundled and sent to users for testing. For participants, all they do is bring up Lookback’s interface and start recording.
For Android, you can gather feedback from remote testers by sending them an email invitation which with a few taps lead them through installing lookback and your app, as well as through recording the whole testing session.
I also found this list of mobile testing tools: https://blog.kissmetrics.com/testing-tools-for-mobile-ux/
Hope this helps