What's a good iOS app for accurately tuning a guitar with various alternate tunings?

Fender Tune: Guitar Tuner App stands out as a reliable and user-friendly option for guitarists needing precise tuning. It's particularly useful if you explore alternate tunings, like those used in Nirvana songs (drop D, half step down, etc.). The app's accuracy ensures your guitar sounds its best, whether you're playing standard chords or experimenting with different tunings. Its simple interface makes it easy to switch between tunings and get your guitar perfectly in tune quickly. Beyond standard tuning, Fender Tune offers a wide array of alternate tunings, catering to various musical genres and playing styles. This versatility, combined with its ease of use and accuracy, makes it a top choice for guitarists of all levels.