Conversocial provides hosted live chat and in-app support and feedback for mobile applications. It is a fully fledged in-app FAQ, in-app feedback, and live chat platform for iOS, Android and PhoneGap apps.
Drift is a great alternative to intercom even though it has come later in to the in-app support space. The costing for the feature sets i needed were cheaper on drift. Intercom can become cheaper if you start taking package dealsIn-App Support Tools Intercom