We don't collect any personal identifying information.
If you have opted-in to analytics on the Android app (thank you - that helps us know what things we need to improve), we will receive anonymized information about user behavior. This includes crash reports, which screens you used in the app etc... Analytics is provided by Crashlytics.
We never capture usernames, the contents of your texts or your location.
This is an open-source project run by hobbyists and we try to be completely transparent. If you have questions on this policy, please post on the forum and we'll reply/clarify/correct.
Keep being awesome!