A mobile stack app is best for clients who will return to the stack often. It gives them a home-screen icon, a cleaner mobile entry point, and a more personal way to revisit the photos.
Use it for high-touch clients
Weddings, birthdays, family sessions, and long-running event stacks are good fits. A quick proofing stack with a short lifespan may not need it.
Use the stack cover as the app icon
The icon should feel personal. Using the stack cover image makes the saved app instantly recognisable on the client's phone.
Explain Safari clearly on iPhone
On iPhone, Add to Home Screen is handled through Safari. If the client opens the link in another browser, they should be told to copy the link and open it in Safari.
Keep the instructions short
The best instruction screen does not over-explain. It shows the app name, icon, and one clear action: tap Share, then Add to Home Screen.