Collaboration app for employees in IOS and Android

Greetings, We are a company looking to have our own mobile app designed to have a secure communication and collaboration between the head office and all mobile employees. The following features needed: ------------------------------------------- - Group of employees need to be connected with latest updates and docs. - Company news and general notifications. - Employee alerts and news. - Employees need a token to activate the app onm their devices, along with registration with their personal info. - A way to sign on some docs (using drawing with their fingers). - Push PDF docs. - Can download PDF docs from company server to be saved or reviewed by employees. - Can send monthly duty-time-plan or roster using PDF or any other format. - Everything need to be encrypted, no exception. - Ability to access docs through website (to check email or latest news - server is CentOS or any Linux server required). - Ability to add more features in the future. Conditions: ---------------- - You must be a company or software house, you need to prove this. (No individuals please) - You must have already made apps published under your company's name in iTunes app store. If you don't have apps published, please don't apply. - There will be a contract to sign. - There will be an NDA to be signed. - Support and debugging cycle for at least a year. - Future added features should be free. - Main platform is IOS, but Android also preferred.