What's a solid iOS app for mapping out new trail runs and keeping track of elevation gains, especially when I'm out in the sticks with zero cell coverage?

Okay, so Gaia GPS has become a staple in my training. As a fitness instructor, I'm always scouting new routes for my clients, and this app nails it. The offline maps are crucial when I'm exploring trails in the Santa Monica Mountains where cell service is non-existent. I can pre-download detailed topographic maps, plot my course, and track my pace, distance, and elevation gains in real-time. Plus, it integrates with my Apple Watch, so I can check my stats between sets without pulling out my phone. I love that it lets me record custom waypoints, like good spots for water or a killer view. It's a solid performance and keeps me accountable, even when I'm completely off the grid. Seriously, a must-have for any serious trail runner or hiker looking to optimize their outdoor adventures.