iPhone and apps

Is it possible to transfer (NOT COPY) an iPhone or iTouch app to another iPhone or iTouch?
I have an app that I inadvertently downloaded to my iTouch but is not well suited to he iTouch. However, another family member has an iPhone that the app is well suited. I would like to give (again not copy or “steal”) them the app so it can be used as intended.

If both devices use the same iTunes account, you can download it on the other device at no cost. If they’re on different accounts, you cannot transfer/copy/move it to the other device unless you log in with that iTunes account.

Yes, as long as - as AaronX says - both devices use the same iTunes account. You can access the apps freely between all devices with the same account - iPhones, iPods, iPads.