Nintendo Switch Parental Controls app
The gentlest console control here, and a free app that links to both Switch 2 and the original Switch. You set how long or how late the system can be used each day, then choose what happens at the limit: an on-screen alarm that trusts your child to save and stop, or an automatic interruption if the alarm keeps getting ignored.
Starting with the alarm and keeping the interruption in reserve is a fair way to hand over responsibility. The monthly play summary shows patterns rather than moments, and on Switch 2, players under 16 can only use GameChat with friends a parent has approved.
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