Sketch

Sketch draws interfaces in a Mac application and puts the reviewing half in a browser, so somebody signing off a screen needs no licence to open it. Editors are counted and viewers are not, which keeps a project's cost tied to the people actually moving pixels. Two ways to pay sit side by side: a subscription per editor, or a single payment that keeps working after the year of updates it includes runs out. Anybody designing on Windows is ruled out, because the editor itself is Mac only.

Standard is $12 an editor a month billed yearly, with real-time collaboration, unlimited documents, version history and free viewers. Professional at $24 adds single sign-on, project archiving and permissions groups, and Enterprise at $44 adds SCIM provisioning and BYOK encryption. Beside the subscriptions sits a one-time licence at $120 a seat that includes a year of updates and keeps working afterwards. There is no free plan, and the pricing page says so in its own FAQ.

A Mac designer or a small product team who want the option of paying once and stopping, which almost nothing else in this category still offers. The free viewer seats make it cheap for an organisation where many people comment and few people draw. Windows designers cannot use it at all, and anybody who needs the whole team editing on mixed operating systems should look at Figma or Penpot instead.