Some Mastodon instances with higher security TLS configurations are not working in Tusky on Android 7.0. This is due to a regression in its system SSL library—fixed in Android 7.1—where the only supported elliptic curve is secp256r1.
As far as I know, there isn't anything that can be fixed on Tusky's part, aside from shipping its own SSL library, which is too big an undertaking.
Sorry to folks who can't use the app because of this.
Tusky 1.1.2 is now out on google play! https://play.google.com/store/apps/details?id=com.keylesspalace.tusky
It primarily addresses crashes and login errors, but there's a few small additions. Also a french translation was added and updated german translation.