Well that was grindy.
Base idea of game is solid. I also enjoyed graphics and story. Length of game is good(22 days i think). Multiple choices when choosing story might have annoyed some(as it causes missing part of story) but I liked it. Felt like choices I make matter. Adjusting difficulty was good property for this game. Boss fight was nice in a way that it brought difference in game.
Game play was horrible. Specialties took unknown amount of time to activate which made on-off regeneration of apples worse. It was never clear to me, when apples should be regenerating. For example, in middle point of boss fight regeneration of apples stopped, no reasoning in inside game logic. Annoyance of all odd behavior culminated in boss fight, which was inherently unfair(which, by itself is okay). Unfair battles would require, that they are actually winnable. At any point I didn't figure out what I was doing wrong, for example, one time, boss just ate all my guys, one by one. Only way I was able to beat it in the end was to halt my killing of boss until I could get enough apples in first part, (in part where apples were regenerating) and with voluntary difficulty decrease.
Also other odd things was that sometimes enemy just appears behind my lines.
Game never left me with a feeling when I lost, that how I could improve myself, I just lost, and would I want to decrease difficulty.
With designed unfairness there shouldn't be this kind of unknown. I actually would have liked unfair aspects of it, if game play was smooth. Just suddenly losing half of your guys, guys you used money to upgrade was unfairness. Boss one-shotting my villagers, trader suddenly not showing up when questioned, both are unfair elements. But those would have been very nice elements, IF rest of game play were smooth. Now it felt like laziness, which I'm pretty sure it wasn't.
Visible load bar for special abilities would give at least idea of how long will it take to activate it. If regeneration of apples was supposed to be randomly on/off, mention it. Digging feels completely off, there is no explanation of it, it shouldn't be just random, and if there was some method to gain better results with digging, that should be explained.