Are these shooting games free?

Yes. They all play in your browser for free, with no download needed and no account required to start.

Which is better for aiming, phone or computer?

A computer with a mouse usually gives more precise aim. Simple tap shooters work well on phones, but fast aiming games feel easier on a bigger screen.

Are they suitable for kids?

It depends on the game. Some are cartoon-style and mild, others are more intense. Look at the thumbnail and description first, and decide whether it fits the age of the player.