You can download SoundMeter X for free. Standard SoundMeter functionality, including the Sound Level Meter and Noise Dosimeter, is free to use indefinitely. For access to more powerful tools and additional features, a subscription is required. You can try a subscription for free for up to 14 days.

Pay once, use indefinitely--ideal when you want to use your device as a dedicated instrument. SoundMeter Pro 2022 will continue to receive maintenance updates through 2025, after which it will continue to work indefinitely on compatible versions of iOS (iOS 14 through the latest iOS at the end of 2025).