customization of the latest version of linphone

I am looking for a highly experienced person to customize the latest versionof opensource [login to view URL] software. everything must be encrypted end to end You will configure client and server side .some other things to be done Including splash screen , network registration, add self destruct messages feature(secret chat) and some layout features..add rotating banner ads system (similar to the one you see on skype desktop ) Apps must be for iOS and android. I have done test with self destruct message feature and it works very well. Linphone is adding this feature in their next version but i need it now. we can use TLS/ZRTP we have to make sure app cannot be blocked in any country. linphone already has push notification but we need to make sure it works very well so calls to the apps with messages are never missed. registration would be done by email only, a new phone number would be added to each registration. App must stay connected when changing between wireless network and WIFI., please respond with links of similar work you have done Please do not waste my time or your time if you have never done this before. Your bid WOULD be the price we pay if you are awarded the project. DO NOT try to ask for more money upfront . Funds would be released upon fully delivered bug free product. NO milestones. If you are about money first, please stop reading .this is only for serious, honest professionals. There are also some special calling features for users in the usa with existing gsm service which will be discussed before starting project. This will not increase the cost of the project. This product must be alive at all times as long as the device is on. Call and all active communication must stave active when devices switch between mobile and wifi network..NO MONEY UPFRONT. If you are one of those people who use excuses like, you have high feaver, your uncle died, ethernet cable got cut. Protest or family emergencies, please stop reading and move on. NO SCAMMERS. I am looking for EXPERIENCE developers who have done this before . i have no time to teach anyone now.