As Dan said, this is a brutal hobby. A whole lot of things have to go right, in order for those pictures to turn out.
In order for those things to go right, a bunch of T's have to be crossed, and I's dotted. If you find yourself thinking "It should just work", or "I shouldn't have to...whatever", then that gets in the way of the crossing and dotting, and frustration ensues. And I know about that, because it was a hump that I had to get over myself.
Visual and Explorestars: I have no idea why the Android platform requires that the db be installed separately, but that doesn't matter, because for the here and now, it just does. I don't use it myself, but there are lots of posts here from other folks asking for help with that, and the separate install step for the db in an SD card sounds pretty straightforward. Easy to dig up.
Astrophotography: You can try unguided for a lark, but guided is simply better and more reliable. These mounts are designed to be used visually and guided. The PMC8 controller and its power train are responsive enough, that, given a mount that's adjusted and balanced reasonably well, the Periodic Error(s) on the mechanical side can simply be guided out, just as Jerry says. And yes, you need a good polar alignment for guiding, but PHD2 can guide around a bit of error.
So how do you get there? By methodically crossing T's and dotting I's. I'm reading one fer-sure installation problem with Explorestars, and AFAIK, it's easily remedied with a little research.
I'm reading a suspected installation issue with APT as well, but can't be sure because I don't use it. I CAN tell you that it cost me a lot of research and fooling around to get my plate solving working, with AstroTortilla. Combination of picking the right version of AT, getting the right indexes downloaded, and setting up its parameters properly. Lots of fiddling about, and sifting good advice from bad on the interweb, but now that I'm past that, it does 'just work'. Anyway... just be prepared to dig in and work the problems...plenty of happy APT users around, and if they can do it, you can too.
Mounts: ES PMC-8 EXOS2
Scopes: SV 102EDT, ZWO 60/280 Guide
Cameras: Nikon D5300, Altair GPCAM2-IMX224C
Software: ASCOM, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer: Thinkpad x230, Win7Pro/64