I deliberately bought my tickets through the app to save hassle and get some small discounts, which was quite good. Once you get there, you just have to show the barcode—it's simple.
There are several shows to see: the Penguin Show, Mermaid Show, Sea Lion Show, Dolphin Show, 5D Cinema, and other fun rides. The show schedule listed in the app is very helpful for planning your schedule.
Friday prayers are also hassle-free; just cross from the Sea World side and you'll arrive at the Baiturrahman Mosque.