I have pop ups in DragCore that will hopefully boost profit a bit. There are 3 of them and they appear only one time each. They come up when the player is able to max out their crystal total by buying the biggest IAP pack available. When the player passes 99 minus the number of crystals in an IAP, the button never appears again. If the player buys something or dismisses the prompt it doesn't appear again until the crystal counter reaches the next milestone.
I also wanted to make them look appealing so I used color and button positioning to make it feel welcoming & friendly instead of forceful and greedy. At the same time I need to emphasize how good the deal is and inform players that after a certain point they can't be bought anymore. The very last promt has different text at the top that reads "Last Chance!" to encourage players who get that far to pay just one measly dollar to save themselves time.
I recognize that foreign countries will not go by the USD depicted on the button sprites, but the numbers are meant to emphasize the value of the deal. When a purchase button is pressed an OS controlled pop-up will appear revealing the local currency for the customer to confirm the purchase.
These pop-ups only appear later in the game, giving players time to get used to the crystal system and understand how it works. Hopefully that minimizes people upset about the lack of instant completionist gratification for their purchase. Buying crystals does not instantly unlock everything, it just allows them to be available instantly after they are earned in Challenge mode.
With the way these are set up the most I could make off of IAP from one customer is $8. Players maxing out by buying will end up paying $6 - $8. I expect most people who pay at all (less than 10% of players) will probably only pay for the 12 pack once and spend $1 total. I hope the IAP prompts boost 3% of that (0.03% of players) to invested players spending $1 each time the prompt comes up, adding up to $3 total.
The breakdown for maxing out crystals through IAP goes like this:
12p - $1; 39p - $3; 80p -$5;
- 8 12p: $8
- 5 12p + 1 39p: $8
- 1 12p
+ 239p: $7
- 1 12p
+ 180p: $6