Cool toys that actually help:). Varigrip is particularly useful as a callus builder in my opinion. It also works well for hand strength and developing finger dexterity for seperate fingers. However, the grip had a somewhat larger girth than any guitar neck, which makes it akward for my pinky to press the button and causes cramps.
The Fiddilink I use as a fun fidget toy for my right hand. I can see that it would help build finger dexterity and flexibilit as well, but otherwise it's already quite a satisfying fidget toy that helps to stretch and relax your fingers after playing:)
