Can I learn one meditation technique properly instead of sampling several?

A Techniques course centres on a single technique for its whole length: breath focus, body scan, visualisation, mantra or sound awareness. You pick the one you want, or let the app choose based on what you say you find hardest. A beginner course opens it up gradually, so a breath course moves from the breath at the nose to the breath at the belly to counting. An advanced one takes the same technique toward whole-body breathing and choiceless awareness. Guidance stays generous throughout, because you are learning something.