> It certainly isn’t a great solution to create a UI that is impossible to understand without tooltips and ship that UI to mobile devices without the tooltips!

> It certainly isn’t a great solution to create a UI that is impossible to understand without tooltips and ship that UI to mobile devices without the tooltips! Right, so don't do that. But, desktop and mobile are different platforms with different input devices, and designers should make use of both to create the best experience for users. There are certainly tradeoffs in terms of cost to implement versus value for users, and if the argument is "it will simply cost us too much money to implement tooltips" then I suppose that's up to the product manager or equivalent. But, "we can't have tooltips on desktop because the mobile version doesn't support them" is a non sequitor. If a UX person gave that as a reason, I'd have some questions for them.