Basically any apps with video. Several Map apps including Google Maps (I know, but it was my 4th app attempt at finding some working maps). Games.
Apps like Reddit work ok, Goodreads, Anki, My bank apps, Storytel all work absolutely fine. Brave seems to work ok-ish.
Here are some starting resources and helper videos I created:
Best regards
Fuchur
Please spend your time learning the interface. SailfishOS is heavily gesture based, there’s a tour app. If you go to the official Store app on your new phone, there’s Android App Support and MicroG that you can install, if you absolutely need to run some Android apps. But for the most part, enjoy and try to embrace the fact that this is NOT an Android phone on purpose.
Later on, when you become more comfortable, you can even explore installing Storeman Installer | OpenRepos.net — Community Repository System as you can find many useful apps there also.
You are not allone. Second Job with a mandatory iPhone now. Works but is in no way nice. I have a lineage phone too as my private idiot phone. Works… Enough said.
When I have problems with YouTube being slow on my Android - I make a Network Speedtest and reload the wifi!
It seems there’s some optimisation needed on the video side. It’s always worked perfectly on my old phones. Android 13 never had these issues. Let’s give them a bit of time to optimise the brand-new implementation of Android 15 
It’s one device with less than 4000 current users developed by a team smaller than button testing departments at Google or Apple. Yes, not everything will be perfect from the start - but as a user of more than 10 years and counting (and being in the trade myself), I gotta say Jolla is doing a decent job weighing resources against issues.
Patience is a virtue. And if you can’t live without instant gratification… well… there are options.
There was ample chance to test drive what you signed up for. Maybe next time just don’t jump on things early where you might get disappointed and lose money.
If you’re looking for maps, Pure Maps in combination with OSM Scout Server is all most people need. But you’ll need to install them from Chum or OpenRepos/Storeman, because the Store versions are out of date.
Like basically all Brand or Store apps they do things like discounts and coupons and games and so on:
I have only tested with Yle Areena and HBO Max and didn’t notice any problems with those, so don’t know what the issue is with other services/apps.
There are excellent native apps available if the Android apps won’t meet your needs.
I would assume anything heavier than your basic word games, sudoku, connect things or draw lines games or something bit older like Angry Birds probably wouldn’t be that enjoyable even on mid prices Android in the long run. But luckily for us, there are some native games also available.
Nice to hear. Sometimes people, who complain how the AAS is crap and with it nothing works properly, forget to mention, that actually some of the apps they tested worked just fine.
I can confirm. At least for me the english autocorrect XT9 doesn’t work at all while writing to this forum through native browser.
i can confirm that the autocapitalisation is not working on this forum also on Jolla C2 with 5.0.1.11. otherwise it seems to work very well.
Oh boy that thread attracted quite some attention over this weekend 
…
Did the community miss an school fight?
Tips for new viral threads: ‘‘Jolla, never again’’, and ‘‘I wanted to support SFOS, but all apps are rubbish’’.
Maybe just as now replies seems to get a little about android apps and JP feedback overall, i’d like to remind, to avoid overthreading, that we have already a thread to help new Jolla Phone users:
And also a lively thread for Jolla Phone feedback:
I think we shall prioritize those 2 threads, for help and feedbacks.
Present one is vehemently tilted as ‘‘no-go!’’, and shall better get replies along that line only.
Disappointement is a derivate of the disparity between expectations and reality.
So: Who is responsible for the former and who for the latter?
I’d like to add another camp that I find myself in. I’m honestly super happy with the new Jolla Phone and I’m enjoying the user experience way more than I did on Android previously.
The thing is that over the years I’ve reduced my smart phone dependency drastically and use cases are rather simple, so perhaps I’m just not facing the issues that others are. All the basic things have worked flawlessly. I’m amazed by some of the community-built apps and enjoy the simplicity of SFOS. Apple and Google have built ecosystems that are convenient, but have also locked people in.
That said, I wholeheartedly agree that the community should be more understanding towards newcomers’ expectations. Jolla simply isn’t for everyone, and by listening to feedback it may some day be.
A welcoming community is another reason to stay!
If being for everyone means becoming more like Android and iOS: thanks but no thanks. I’ve seen too many FOSS projects become like established alternatives, I don’t need my cellphone go that same route just because some newcomers think they know better.
I might not agree wit everything you say, but +1 for the keyboard autocorrect. Of course there should be option to disable it, but for someone writing not their native language with semi bad dyslexia it would also be big help. I can workaround that by confirming every word but takes time
Videos currently have known bug and there has been confirmation from Jolla that gmaps should also get to working state. So expect those to get better Soon™…
Serious question, what else do you expect?
What annoys me personally in the interaction with new users are the “have you search the forum” answer.