I am nearly done with Picross e3, which will mean a purchase of Picross e4 in the near future. In the meantime, though, I was pointed the way of Pokémon Picross, a free-to-play 3DS game which uses the same mechanics as the e* games but with puzzle solutions based around Pokémon. Obviously.
It's not quite the same. The backend is the most different - rather than just selecting from a menu, there's a sort of story attached, where you have to travel from area to area, solving the puzzles and collecting picrites. You get a certain number of picrites for solving puzzles, but also for meeting various conditions - enabling certain powerups, meeting the time limit, and so on.
Powerups are another difference. You can equip a certain number of pokémon, who will then give you things like a random row reveal, freezing time, or showing you where moves exist - like in the e* games, with blue colours. To be honest, I don't really use these - except you are forced to do so in order to get the maximum number of picrites. It would make more sense if you got more for not using powerups ...
But maybe not from a financial point of view. Your powerups can only be used a certain number of times before needing to be recharged - basically, they're out of action for an hour or so. You can always pay picrites to recharge them quicker. You have to pay a certain number of picrites to access the next area, but there aren't enough in the puzzles themselves so you have to do the daily challenges - earning a few each day. Or you can just buy picrites for real money,
So everything seems to be geared up to get you to spend picrites. It feels like you're constantly being badgered to give the game more money, or wait for another day or another week before you're allowed to have any more fun. Have lots of fun! But only a certain amount each day!
The odd thing is that there's an option to buy a bundle of picrites which are unlimited, which would effectively make the game a standard pay-for title. But I resent paying for that, and instead am chipping away at the daily challenges in order to open Area 4. I think it may be because even when using a virtual currency, buying things in-game always stresses me, so I don't like the backend structure of a game that's based around that.
Finally, an exercise for the reader. I had trouble with this - where is the valid move? It took me 20 minutes to find it, but there is indeed a definite place to go.