We usually share our app screens InVision. It's great. But it's tricky if you want to keep a catalogue of previous versions. And it required a bit of monkeying about and testing it all works etc.
An alternative quicker method is to attach app mockup screens to an email. Clients can swipe through the attached app screen mockups quickly to get a feel for it.
Can you recommend any other tools for quickly sharing a flow of screens to clients viewing on their mobile phone? The key thing is being able to swipe through screens without fiddling with selecting files, and without any administrative debris hovering over the image when viewed.
And, how do you handle cataloguing previous or alternative versions of the flow?