OpenJDK finally ported to iOS

Someone Johan has recently "run an application using Gluon Charm (Material Design UI controls) on top
of JavaFX (OpenJFX 9) on top of Java on my iPad mini, so this is a real-world complete stack."

MobileJDK is still under heavy development, however it is a good result! Port to is achieved with Zero interpreter due to the fact that Apple does not allow dynamic code generation on iOS.

Details here: http://openjdk.java.net/projects/mobile/ios.html

Tox - open source replacement for proprietary IM protocols (such as skype)

Tox is an open source instant messaging protocol supporting text, sending files,
video chats and so on.

qTox, µTox, Antox, Toxic, Antidote and others
are open source clients for this protocol.

Available on Linux, Windows, Mac OS, Android, iOS
and anywhere you ready to port it
https://tox.chat/

Unlike Skype and ICQ Tox using decentralized DHT network for p2p communication.
User ID (hash) looks like
0ECA261D206B8D3899A8B0B751BF37206E3CCD73ACE2C4C3B79A9CB9505B301C642D14F43AD7

Tox FAQ:
https://wiki.tox.chat/users/faq

Here's a list of Tox bootstrap nodes for DHT network:
https://nodes.tox.chat/

There's also so called ToxDNS for shorter and human readable contact names.
It is possible to use 3rd party DNS or to establish own one:
https://wiki.tox.chat/users/toxdns
(it is considered to be less safe than hash, however if you control own DNS it should not be a problem)

Link to the Tox Core repo:
https://github.com/irungentoo/toxcore (crossplatform C)