Application for a personal trainer: clients, plans, progress

I'm a personal trainer running my entire practice from my phone and a pile of spreadsheets, but this approach no longer works as I grow. I need a proper coaching application built around my clients: a database where each has their own card with goals, injuries, notes, and assigned plan. Directly from this database I want to build individual workout plans exercise by exercise, with sets, reps, tempo, and rest, change the order and swap movements as they progress. Nutrition is equally important, so clients should keep a food log relative to daily targets I set, and I want to see who actually hits their numbers and who falls off.

Progress tracking is the heart of everything. Each client logs body measurements and weight over time and uploads progress photos from the same angles so we can compare week to week on a clean graph. I want charts where the trend is obvious at a glance, not raw numbers to squint at. Plus I run live and video sessions, so I need a calendar with booking, reminders, and simple payment for both single sessions and monthly coaching packages. This is a coaching tool around my clients and their results, not a gym management system or a generic workout log.

Please treat this as a focused first version that I can give to real paying clients: clean and reliable, not cluttered with features. Mobile version is mandatory — most will open it between sets. Happy to provide references, my plan templates, and an exact list of fields I track, and want to review screens and data model with you before development starts.

— Client database with goals, injuries, and notes for each
— Plan builder: sets, reps, tempo, rest, order
— Food log relative to set daily targets
— Progress photos, measurements, and weight on a unified timeline
— Session booking with reminders and package payment