Guitar Tuner - Ukulele & Bass 4+

DoubleTune: Tune Violin & More

Gismart Limited

    • 4.4 • 7K Ratings
    • Free
    • Offers In-App Purchases


DoubleTune is an advanced tuning app created by professional musicians. It’s suitable for tuning a range of string musical instruments, learning new chords and refreshing your memory of already-learned ones. Competitive educational games are equally useful for beginners and mastered guitar players. One way or another, DoubleTune is a must-have app for any musician.

Made by experienced guitarists, it is simple, fast, intuitive and accurate. It’s perfect for tuning acoustic, electric and bass guitars, along with ukulele, banjo, violin and cello.

- Choose between a range of tuning presets and modes:
- Tune Guard™;
- Standard and Popular tunings (6 and 12 strings);
- Drop and Double Drop;
- Open, Modal and Lower;
- Ukulele tunings;
- Bass guitar tunings;
- Chromatic tuner;
- Auto and Manual modes;

Tune Guard™ is a smart feature that helps you tune safely. It warns you with both visual red signal and string highlighting when this string is too tight and is about to break. The mode is designed to help beginners and inexperienced musicians save their strings, time and money.

You can easily tune:
- Electric and Acoustic guitars;
- Western and Classic guitars;
- Bass 4 and 5 strings;
- Ukulele;
- Violin;
- Cello;
- Mandolin;
- Viola;
- Balalaika;
- Banjo;
- And any other string instruments.

Get the most out of DoubleTune games:
- Learn chords! Hone your skills and get familiar with many of common chords. These entertaining games focus on chords and chord diagrams. You can easily transfer this experience to real guitar playing!
- Ear training. Learn basics of guitar music theory in a fun way. Master your musical hearing and chord recognition ability with the help of quizzes.
- Stay competitive and try to get the best score in less time!

Great for professional and beginner guitarists! Enjoy tuning your instruments at the astoundingly high level.

The app contains the following subscription options:
- Weekly with a 3-day free trial at $3.99;
- Yearly with a 7-day free trial at $21.99;
- Weekly with a 30-day free trial at $3.99;
- Music One weekly subscription with a 3-day free trial for 9.99/weekly.
- Payment will be charged to iTunes Account at confirmation of purchase.
- Subscription automatically renews unless auto-renew is turned off at least 24-hours prior to the end of the current period.
- The account is charged for renewal within 24-hours before the end of the current period.
- Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user’s Account Settings after purchase.
- The cost of renewal is equal to the value that “Apple’s App Store Matrix” determines as the equivalent of the subscription price in $USD.
- Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication.
- You can subscribe for unlimited access to our PRO services:
* Tune Guard™ for safe tuning;
* all instruments;
* all games.

Privacy Policy:
Terms of Service:

*Price are equal to the value that "Apple's App Store Matrix" determines is the equivalent of the subscription price in $USD.

* Tune Guard™ feature does not guarantee 100% safely tuning. Gismart Ltd. takes no responsibility for causing any damage to your strings.

What’s New

Version 4.31

We’ve made some app stability improvements and fixed the bugs reported by our users. Keep the app regularly updated to always have our greatest features!

Ratings and Reviews

4.4 out of 5
7K Ratings

7K Ratings

Kolys37 ,

Does exactly what it says on the tin

It's a guitar (and ukulele) tuner. Whether you need a reference tone, a chromatic tuner, or to tune to a standard or common tuning for the instrument, this app gets it done. Nice UI, very intuitive.

The only reason I'm giving it four stars rather than five is that if it could also handle bass, mandolin, banjo, bouzouki and other stringed instruments in the same way as it handles guitar and uke - or if it allowed me to create a custom tuning of my own in order to mock up the mandolin or banjo - it would fit my needs perfectly.

UPDATE: since my initial review, 12-string guitar and 4- and 5-string bass have been added, and this app has absolutely become my go-to for tuning, and I’m bumping it up to five stars for that. If the mandolin and banjo could be next, it would be absolutely perfect.

superseth88 ,

What a shame, and the developer clearly doesn’t get why

Been a minute since I picked up my guitar and ukulele. This was always my go-to tuner. The free version. The one you could click to avoid a trial by clicking the x in the top corner or whatever it was. Now you are forced to either use the free trial of death ($8/week after three days) or pick a new app, which I will be. If this app is making money, it is by scamming people who either do not realize there is a weekly fee, or didn’t remember to cancel their trial. No one would knowingly pay more than $400 a year on a guitar tuner app masquerading as a free service on the App Store, and Apple should honestly do the right thing and remove the service like they did other insane fee charging apps.

What makes it worse, and the reason I’m bothering to write a review, is that the developer clearly either does not understand or care based on their responses to other reviews on the matter. We aren’t daft; we understand what a three day free trial means. We understand we can cancel it, but what is confusing is that you would purposefully neuter your app and then act completely ignorant as to why such an insane and immoral change as a forced premium-to-use model and sketchy free trial period/fee would upset years-long users.

Developer Response ,

Hi there, thank you for such an in-depth response! Your feedback is essential for us to continue improving Guitar Tuner. In fact, we'd love to hear more from you directly. Would it be possible to drop us an email at Our team would love to hear some more of your great ideas! Speak to you soon!

Awesomepal ,

Ridiculous. Also I’m salty.

This ridiculous, for lack of a clean word to use that truly shows how ticked I am, app refused to let me bypass their intro without subscribing to their premium “trial”. The “trial” automatically begins drawing money after it is over and is darn (again, lack of a word) near impossible to turn off. How do I know? My second plan after closing out the app and clicking back on it again (The intro only appeared again) was to sign up for their subscription and immediately cancel. The instructions say you can close it out through iTunes. Okay, 1. iTunes is an incredibly hard platform to manage, as anyone without a computer science degree who has spent five minutes trying to work the thing out will agree with. and 2. This is an APP. iTunes is for music! That’s why it had “Tunes” in the name! And lastly, I DON’T HAVE ANY MONEY TO PUT ON MY CARD TO EVEN SIGN UP FOR THE THING! I’M DOWNLOADING A FREE GUITAR TUNER APP, DO YOU THINK IM ROLLING IN DOUGH HERE? ALSO, THE PREMIUM FEATURE IS $8.00? Seriously, this app is ridiculous. Maybe if they got rid of this marketing scam at the beginning of the app I would be able to actually see the rest of it, including the actual tuner portion. DON’T BUY UNTIL THIS SCAM IS OVER.

Developer Response ,

Thank you for the time spend on sharing with us your user experience. Please accept apologies for all this inconvenience. If your intention is to unsubscribe, please follow the link for a step by step guide: But you can also enjoy our free version of the app choosing a limited version of the app. You're always welcome to contact us at for the assistance. Have a nice day!

App Privacy

The developer, Gismart Limited, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Used to Track You

The following data may be used to track you across apps and websites owned by other companies:

  • Purchases
  • Identifiers

Data Not Linked to You

The following data may be collected but it is not linked to your identity:

  • Purchases
  • Identifiers
  • Usage Data
  • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Some in‑app purchases, including subscriptions, may be shareable with your family group when Family Sharing is enabled.

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