I've provided some useful links to our documentation surrounding our Okta Mobile Management solution that I'm confident should answer your questions. We offer support for implementation and online webclasses for training. If you'd like to test drive our mobile solution or any of its features, please feel free to open a support ticket and we'd be happy to assist you getting started.
Support for distributing internal iOS apps was just announced at our Oktane conference this week. Please email firstname.lastname@example.org if you'd like to participate in the beta.
Support for distributing Android apps will come soon as part of our support for Android for Work (also announced at Oktane). With Android for Work, we will be able to distribute both custom and public apps through Play for Work, which can be customized to include only the apps that your organization wants to make available to users.