Personalisation LinPhone Security & Design

We are in a need of a customization of the opensource VoIP / SIP client LinPhone. The development has to be done in two phases: Phase 1: Customization of mobile + tablet apps (iOS + Android) // Objective C = iOS + Java = Android --> ready in two weeks. Phase 2: Customization of PC apps (Windows, Mac OSX and Linux) // Qt/QML = Windows, Mac OSX and Linux --> ready in four weeks. The main customization's must be: - Upgrade security Many security features, which include i.e.: --> Use TLS connectivity for handshake --> Use VPN connection for additional security --> Use ZRTP encryption protocol on VoIP (voice and video) communication --> Use text encryption for messaging and file sending --> Database security on app and server --> Secure connection settings --> Use code obfuscation protection + Sign the app --> Harden the security of application / program --+ Encrypt the entire application --+ Containerize the entire application --+ Encrypt the database --+ Lock screen / Login protection --+ Brute force protection --+ Code hardening by Pro+iX Guard --+ Store encryption keys securely in Trusty --> Set privacy settings - Design customization Many security features, which include i.e.: All designs are based upon the operation of LinPhone, almost no real custom development. --> Add a lock screen / login screen prior using app --> Every function in the LinPhone app is customized by designer --> APP settings are blocked for users to change - one setting fits all --> Custom user account settings SIP server will be setup by an other person if this isn't your specialty to save time and costs. When you can do this also total project budget is 1200$. Budget $750 - $1000 for entire project. Ready in 2 - 4 weeks (divided in two phases) Time is of essence and must be ready in 2-4 weeks.