you can open the back of the phone while it is on. On older phones, I would remove the back and pull the battery while the phone was on if the phone "froze" up and I couldn't get the phone to work. Not likely you could hurt anything by removing the back cover.
Is it safe to open and look around stuff inside back of phone while it's turned on , or is there something like a laser (ir) that can harm my eyes / me ? I obviously know not to touch stuff since you can get shocks.

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