Hootsuite is a good app with multiple use features and we can certainly build a similar app for you on iOS. We'd like to use objective C to build the app.
We'd integrate APIs of Social Media to pull in all required posts and you be able to send posts for clients.
A web based user friendly ADMIN PANEL will also be built to let you manage/update the contents.
Features like User Profile registration- (also using Social Media accounts), Dashboard, Messaging, Posts, Create Organization, Import Contacts, Invite Colleagues, Streams, Feeds, Blog, Feedback, Google Maps API, Assignments, Ads, Scheduling etc. will be integrated and incorporated within the app.
The App will be Mobile Friendly and will run seamlessly on all versions of iPhone / iPad & devices.
Finally, after the completion of the project we will assist you to host the APP in iTunes Store and provide you an 3 months of Free Support upon completion.
Also, we will provide you full source code.
So please PM us so that we can get into a brief discussion with you. Hoping to hear from you soon.