We have multiple apps, but I'll share only the free ones; the others are B2B (they haul in major revenue for us, and businesses dealing with us will not like us disclosing this here), largest free one is MacroCodex with 17,000+ users.
We do not have this problem; we heavily use the models from OpenAI and Anthropic, but we have a custom harness built for ultimate cache efficiency and a purpose tuned workflow.
Codex is GREAT but it keeps updating and its UI changes often (remember mini git sidebar ui?)
Our Custom Harness does multiple things, like having a "Skill Selector," which uses our Gambler v1 (26B decision model responds in <100ms locally) and overlays tools on top of existing ones (as the models are RLVL over the specific tool in their harness, we overlay those tools with a familiar interface or format and inject custom features we want the model to interpret). Other than this, it leverages local models to accelerate development. Also, instead of providing custom tools, we actually use the same tools that their original model-provided harness uses. We've a list of 100s of such optimizations; these are just a few from the top of my head.
I have been working on harnesses for a very long time; I read research papers and implement them.
The apps use Flutter and Rust for all of our apps; no ads, no subscriptions.
So, macrocodex is basically a neural network product which "predicts" maintenance calories at a very high accuracy, https://macrocodex.app/
MacroCodex beats everything in its category and it does it for free, no ads, no subscriptions.
Symbiote and CalorieCodex will soon follow the suite.
If it fails, people get fat instead of losing weight, or get skinny instead of gaining weight.
Recently, we launched CalorieCodex (a calorie tracking app with an optional Full Agent Harness, where an agent tracks calories for you) and Symbiote (a programmable workout app; think BoostCamp, but user-programmable so it can run any bodybuilding program).
You can find some screenshots here:
https://macrocodex.app/guides/peak-week/