The new version of the Hydrocarbons app has been approved after 6 days of waiting and just 1 min of reviewing.
The major reason of the update was to add “promo nodes” (links after questions) to my recent apps. I moved the “Watch Ads” button from the Settings to the game as well, though it seems that the whole idea with interstitial screen ads doesn’t pay off in my case. There are several minor fixes in chemical formulas in their style or sizes. In the main menu, I highlighted that two locked modes (“Dienes & Polyenes” and “Polycyclic Aromatic Hydrocarbons”) can be unlocked (= bought) in Settings. The word “Buy” near an inactive button was a bit confusing. The letter keys were made bigger in case of iPhone/iPod. The sounds of correct letters now grow in their pitch which is not as monotonous as it was in 1.0.