Is Allo using the same code, or a different implementation?
(And it's not so obvious to me. The thing I linked is licensed under GPLv3 + MPL if used on the App Store. You can totally ship an Android app that runs a separate GPLv3 subprocess, and an iOS app that uses it under the terms of the MPL. The GPLv3-subprocess thing is what JuiceSSH does for running Mosh.)
(And it's not so obvious to me. The thing I linked is licensed under GPLv3 + MPL if used on the App Store. You can totally ship an Android app that runs a separate GPLv3 subprocess, and an iOS app that uses it under the terms of the MPL. The GPLv3-subprocess thing is what JuiceSSH does for running Mosh.)