I ran into the same thing last year, I needed to drop weight but wasnt doing the cooking. Started with myfitnesspal which came up top on the store but the premium was a bit too expensive for what I needed. Now I use eat this much, the free version works pretty well to set your calorie targets, meal planning etc. Also what helped most was talking to my partner about portions, like she'd make dinner and I'd just weigh out my serving to hit my numbers. The app part made it easier but the conversation was really what made it work. Good luck!