A user should be able to enable or disable the following:
1. Screen Shot.
2. Camera and Video, even voice by using it purely for messaging.
3. Add a VPN or a way of masking the user's IP address/information as the icing on the cake.
Lastly to make this a truly one stop app, your development team should include the option of also sending encrypted SMS via user network, just as in making use of the ordinary SMS text messaging just like the app called "SILENCE". If your team achieve all these ideas then you have a winning app that can compete with the very best. Basically mould this into something that the government would instantly hate by the mere mention of ODIN. Increase the encryption algorithms more if possible, reason being that the CIA and the NSA all have supercharged computers that can break serious codes within 24 hours to a week. ODIN CHAT should be built to defeat that by not being able to crack the encryption even in a 1,000 years.