Memorizer

The Memorizer is a tool introduced in LittleBigPlanet PS Vita, and then later added to LittleBigPlanet 2 and LittleBigPlanet 3 by the DC Comics Premium Level Pack. It's designed to remember the state of a signal, even if the player leaves and re-enters the level, and, if given a label, can even share the signal across multiple Memorizers with the same label, even if the Memorizers are in completely different levels. A maximum of 50 labels can be created per-profile. This is useful for saving progress in a game, or remembering purchases from a shop.

In LittleBigPlanet 3 on PS4, the Memorizer is completely unobtainable without either importing it from PS3 or hacking the game.

Managing Memorizers
If you have played a community level that uses a Memorizer that is need to get rid some of them for room for others, you can manage then in the settings. You can remove memory of a memorize from a user only; not for each level. You can also "protect" memory, which makes it that the user cannot remove it without unportecting it. Selecting "Delete All Unprotected" will remove all memory from each unprotected profile.