For those who need help, I just use simple math and and chance Note the markings are very helpful, and should be used most of the time. These are the steps I usually do.
1. Flip all row/columns with 0 voltorbs. (If there are none *higher levels* flip the row/column that contain the lowest # of Voltorbs.)
2. Mark ALL cards not flipped with ALL possible outcomes (1-3 and Voltorb)
3. Check on the hints and reduce the possibilities. (Row)
Example, you have a row with 3 points and 4 voltorbs, obviously the only # possible in the row is a 3 So mark the whole row with voltorb and 3 only.
4. Same as step 3 except check with the columns (3 and 4 are interchangeable)
Usually after this, I have flipped all of the 2/3 or is very close to, if there is a lot of cards faced down,3 use your best judgment to randomly select a card.
For this I check the probability of finding a voltorb. Example, a row/column with x points/ 1 voltorb and x points/ 1 voltorb has a lower chance of having a voltorb than a row/column with more voltorb count.
It's best to flip a row/column with more points since there is a better chance of getting a 2 or a 3.
*Note never flip an 1. There is no point in flipping something if you know it's an 1 or a voltorb or an 1. Since the main goal is to find all the 2 and 3s in a set, flipping an 1 is useless most of the time.
If you follow the steps you should be able to rack up some coins fast, at least I did. Usually 4+ wins in a row and occasional losses. I also found myself entertained more while playing lol.