Volatility — Low vs High
Low-volatility slots deliver small wins frequently and your balance lasts longer. High-volatility slots pay out big wins less often, but when they do come the amount can be significant. Which type suits you depends on how long you want to play and how much risk you are comfortable with.
What RTP Tells You
RTP, or Return to Player, is the theoretical average return on every bet over the long run. It is not a guarantee, but it is useful for comparison. For example, Mahjong Ways 2 has a maximum RTP of 96.95%, and Fortune Mouse has a maximum RTP of 96.96%. These figures give an idea of how generous a game is relative to others.
Matching Theme and Budget
If a theme holds your attention, the experience is more comfortable. On the budget side — choosing a game with a low minimum bet lets you play for much longer on a small balance.