Thanks for good insight in to this topic.
As mentioned in my first email, there are a number of reasons for trying out custom encryption schemes. Low-end android devices is just one of them. There is a huge market for low-end android devices in south and south east Asia for example, where over 35% of world population lives. The people there are poor and don't have much understanding of latest cutting edge smart devices and related technologies. Big brands like Apple, Samsung, Nokia etc. are virtually non-existent or have so high price that people simply can't afford them. So cheap Chinese and Indian cell phones which barely run Android are considered "smart phones" and are very popular here. Using SSL, TLS, DTLS etc. are nightmare on these devices.
The other reasons to develop and try out custom encryption algorithms are voip blockage by GSM providers in various Middle Eastern and European counties,
Nearly all encryption algorithms are defined and advocated by US and UK intelligence agencies and it is quite obviously possible that they either have crack or backdoors into them. So, we can't blindly trust them anymore and should look into defining our own algorithms and security standards.
Just to note, i don't claim that ITV or any other custom encryption discussed here can or would resolve all these problems. The main focus is on trying something new and out of the box to improve the voip and network security conditions. I find Kamailio as open source SIP server and doubango as open source SIP SDK as best platforms for these efforts and experimentation.
Thank you.