I'm certain letters are necessary for a 5x5 or 6x6 board. M is better than 16,384, and Z far better than 67,108,864.

Why? Instead of A, B, C, you can go with 1, 2, 3. Ie use the binary logarithm of the numbers.

Good idea with the simple numbers, and certainly necessary to use some tokens other than what this 2048 app uses so we can have a version of it in a 5x5 or 6x6 grid.

When you wrote "Good idea with the letters, but perhaps not necessary. People are happy with simple numbers. Just look at Sudoku which doesn't use A to I", I thought you hadn't noticed my mention of the larger grid, which was really the main point of my comment and maybe I should've worded it differently. Though if you'd begun your comment differently, i.e. "Good idea with the larger grid, but perhaps the letters aren't necessary. People are happy with simple numbers. Just look at Sudoku which doesn't use A to I", I wouldn't have felt the need to reply to correct a perceived communication mistake.

Oh, for a larger grid, you might want to have letters anyway, because your point still applies.

It's interesting that log_2 2028 is just above what you can represent in a single digit. That's very close to merging two 9s.

I'd like to actually see someone pit x, log_2 x, and letter(log_2 x) against each other in an A/B test of the game. The latter two are simpler, but the former might be more exciting, because of bigger numbers.