it depends on how much money you have. if you dont have enough money for photoshop, use paint . net as its free and still powerful depending on the type of ui. have enough money? go for photoshop
edit: firewolf mentioned a good one, which is gimp. gimp and paint . net also is free!
Not a significant development discussion and it seems you’re looking more for a concrete answer, so I’ve sent this over to Art Design Support. Please use this category if you’re looking to resolve very specific design issues in your game or if you are looking for help with design.
It depends on what alternative you’ll willing to learn Studio and other free softwares can produce high quality UI designs, there isn’t a wrong or right software to learn how to make UI.
Affinity designer or Inkscape, are free options you could go about and choose from it provided a bunch of tools and brushes and more whether you’re going for purchases options or free ones they produce similar designs and a cleaner interface. I’m assuming the payed option is a more skilled software if you’re willing to dive into that program.
There’s a bit of a learning curve and it’ll take time to learn how to make decent quality UI whatever program your willing to use it produces similar looks as any other software out there.
I suggest you take a look at a few resources/ tutorials and see how to get started into making UI. It might help you choose your option.
is not free, it’s paid, but it’s a one-time purchase. I think the price has gone up a bit recently, but it’s still good software and is my personal go-to.