Actually, the Bartlett KilnAid and Skutt KilnLink apps both have paid subscription plans, they just aren’t actively advertised and don't include nearly as many benefits as TAP Kiln Control Mobile.
Actually, the Bartlett KilnAid and Skutt KilnLink apps both have paid subscription plans, they just aren’t actively advertised, and they provide a very limited feature set – neither app includes functionality for remote kiln control. Additionally, TAP Kiln Control Mobile offers a free and paid plan, with the free plan covering all the same features and functions (and more!) that you’d get with KilnAid or KilnLink.
For a full comparison of the apps and controller features between various kiln controller manufacturers, check out Temperature Controller Manufacturers Side-by-Side Comparison.