Transferring data and files from OnePlus3 to Galaxy S8

Factual Questions
1

I’ll try to make this concise. I switched from a OnePlus 3 to a Galaxy S8 tonight. When I got home I found that Samsung hasn’t updated the Smart Switch app to Oreo yet. The OP3 updated to 8.0.0 a month ago so I can’t download it to the old phone. I tried NFC but doesn’t seem to do anything. When I logged into my Google account the contacts transferred, but that seems to be it.

What I’m primarily trying to do is transfer things like pictures (which I could save to Drive and download again but looking for something faster), text history still on the old phone (using the stock messaging app), and the biggie-app settings and history. For instance, current progress in games, downloaded audiobooks from Tune In, etc. I thought everything was backed up to my Google account, but it either isn’t or I can’t figure out how to restore on the new phone.

So the question dear Dopers, is how would you go about transferring every possible piece of info from the old to the new? App that does is all for you? A combo of apps? Spend half my weekend at T-Mobile store having them do it? Any help is appreciated.

Oh, and the OP3 doesn’t have a memory expansion slot.

Thanks

2

When I switched from an LG to a BLU, I used Bluetooth to transfer my files. You can transfer multiple files, and it didn’t take long to transfer even a few hundred files. As for game saves, don’t most online games save your info in a cloud? I was able to keep my games progress in the Sims Freeplay and Futurama: Game of Drones by saving to the cloud.