Simple Theater
Email ArosemenaApps@gmail.com. Telling me which device, which iOS version, and which Plex Media Server version you are on usually saves a round trip. Settings → Diagnostics → Export Diagnostics produces a file with no titles, addresses, or credentials in it that you can attach.
Simple Theater shows exactly what Plex shares with the signed-in account. If a library is missing, the server owner needs to share it with you in Plex; the app cannot see or request anything beyond that.
Your server decides how each file reaches your device: Direct Play when the file is something the device plays natively, Direct Stream when only the container needs changing, and a conversion otherwise. Playback Info (the ⓘ button in the player) shows which one is in use and why. Choosing "Original" under More → Quality asks for Direct Play whenever the server allows it.
The server owner controls whether a shared library may be downloaded. Simple Theater cannot grant a permission your server has not given you.
When your server is on the same network, connecting directly is faster and more private than going through the internet. If you decline, the app uses the remote route Plex provides when one is available.
Settings → Account → Sign Out removes your Plex sign-in and keeps downloaded files; removing downloads is a separate, explicit choice under Downloads. Settings → Reset App returns the app to first launch and lists exactly what it removes before doing so.