[Android Apps and Games] Vesem:
Well, that answers that one. For the record, the wording in the list of Pro features might benefit from a little clarification on that point. The list on Github mentions "Notifications per account" and "Notifications with message preview", but neither of those really indicates that free users won't see even basic header info in notifications.

There's some truth to that, sure. On the other hand, I'm not the first person coming here to the support channel to ask how to disable the message-preview-in-notifications behavior. So... the lack of option can clearly result in extra support questions too, as users show up wanting to know "How do I turn off x" and "I can't find the option for y" and "why can't I z".

I guess one way to handle this specific one would be if a user disables "Show message preview" in the Display options then make it apply to notifications as well. Or have one of those heirarchical options, where there's a "compact view" display option, and if you turn on "compact view" the option for "compact notifications" becomes available right below it.

To me, it seems weird and counterintuitive for an app that supports disabling message body preview in the main inbox view in the app itself to then force that same preview on me in notifications. Don't most people expect less detail in a notification than in the app screen that comes up when they tap the notification?

Also, maybe this is my decades as a Linux user talking, but I like options. Lots of options. Give me all the options. I can't imagine I'm the only person who expects that a piece of software specifically highlighting open source as a selling point will be designed to empower the user by letting them configure it the way they want, not to corral the user into doing things the way the developer thinks they should want to. I don't mind having a regular options screen and an Advanced options screen, or a "these options are dangerous and I really think you shouldn't touch them" warning, or bury the options you really don't want me to change in a config file I have to edit by hand! (As long as it's documented somewhere.) But I've always found that as long as you have sane defaults, and the options are a) laid out in an organized way and b) informatively named, preferably with a little explanatory comment on each one, then you can pack in a lot of flexibility without making things confusing. Apache's configuration options? That's confusing. An e-mail client that already supports compact view in the inbox also having a ticky-box for compact view in notifications? That's basic configurability that users (especially ones who are accustomed to open source software) will expect to have available, and its absence is confusing.

On the subject of options being laid out in an organized way:

Have you considered making the "Setup" screen into a first-run wizard, instead of having a whole screenful of numbered preliminary setup steps that are all checkmarked as "done" be the thing that comes up when a user hits the gear icon expecting to see the actual options? Then, many of the things you currently have under "Advanced Options" could simply be "Preferences", and the buttons to add and manage accounts and identities could be consolidated right in there under their own headers. Honestly, having the gear icon take me to a no-longer-relevant numbered list of initial setup steps (with three out of the five being dead weight, given that #3 and #4 are grayed out and #5 is simply a link back to the inbox I just came from), while basic display preferences are tucked away in an "advanced options" screen, seems way more confusing to me than a long list of sensibly-named configuration options ever has.