Open 0xr.space in Chrome on an Android phone, press Scan on the dock and point the camera at a chess board. After a few seconds it draws the board's lines on the picture, and once a position holds, a chess engine's three best moves as arrows, green for the best, each with its move and White's score, such as e2e4 +0.31.
It is experimental. A board seen from above reads best; from a steep angle with an unfamiliar piece set, up to one square in five can be misread, so following a game from the start works better than reading a position cold. Moves are written square to square, not as Nf3. It does not read the board on an iPhone or in Firefox.
No. Taking an engine's moves during a rated game, a tournament or an online game against a person is cheating under FIDE's and chess sites' fair-play rules. Use it to study, to set up puzzles or to go over a game after it ends.
See the privacy page at https://0xr.space/privacy/ for what the camera features send and keep.
Arrows come once the same position has been read twice in a row. A hand over the board, glare, or a board cut off at the picture's edge holds them back.
It turns on by itself when a board is seen. Open 0xr.space/?chess=off to keep it off, or 0xr.space/?chess=on to look for a board as soon as Scan opens.
No. It only shows the best moves for the position on the board; you move the pieces.