A fast-draining iPhone battery, even at 100% health, could be due to software issues or heavy app usage. Before sending your phone in for repairs, try to update your software, limit background app activity and adjust your screen brightness. If these steps don't work, it's likely a hardware issue. Beware of non-professional repair services, as they could void your warranty, use cheap parts and risk further phone damage. At iRepairGuys, we offer professional, high-quality repair services that preserve your warranty. Our Huddersfield branch, as well as our online mail-in repair service, are ready to help fix your battery issues with utmost credibility and expert solutions.