[Starseeker]

Hello,
I don't know of such apps because I don't use them, but I have some other suggestions if I may
First of all, have you thought about making a health check-up? If you've been gaining weight rapidly, it might be a result of an ailment, for example something wrong with how your thyroid's functioning.
Second of all, how about consulting a dietician? They will take into account more information than an app could, such as your average physical activity, job, health condition, food preferences and other needs.

If you still prefer to carry on with a home diet, I suggest cutting out artificial foods completely (sweets and salty snacks, as well as soft drinks). It may turn out that this alone will help you lose some weight or at least stop you from gaining it. If you want to go further - as little unhealthy fats and empty carbs as possible, as little coffee/alcohol as possible etc. (rules of an average more-or-less healthy diet). Drink lots of water. If you could add physical exercise, that would be fantastic.
I hope I helped a bit good luck with achieving your goal.
xoxo S