Hey thanks Adobe that you want us to pay for an app on an external device to have a feature that should've been in Photoshop long ago. Customizing the toolbar has been requested multiple times by myself and others and infinitely overlooked by Adobe. Why you would think a sensible solution is to require tapping on an external device is beyond reason.
Are you in touch at all with the screen resolutiuons that are standard now that allow for and almost require a scalable and customizable toolbar? I can have an endless number of workspaces, customize the hell out of the menus and keyboard shorcuts but not the most utilized part of the interface. ABSURD! You go to so much effort to implement or update obscure features and continually overlook an instrumental piece in the daily workflow of PS.
It doesn't take much imagination to see the overwhelming benefits this feature would offer. Try focusing more on how your customers are using the product and not how many things are in it to use. Expecting people to integrate an external device and take their focus away from the screen where they are designing is unthinkable. That's akin to using a Cintiq to only switch layers!!
Come on guys...other apps like PSP and Corel Paint have had this ability for years. Yes I understand there are keyboard shortcuts and quick keys on Wacom tablets but reality is most users do quick interchanges between keyboard and clicking the tools depending on the task at hand. Having toolbars we can customize to our workflow just like the workspace is a natural element to efficient use of Photoshop and other Adobe apps.