Comparison

Guitar Machines! vs OpenString

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Guitar Machines!

Learn fundamental guitar theory with four interactive "machines." Visualize notes, scales, and arpeggios on the fretboard, and even see song progressions. Designed to help you master guitar playing.

Highlights
  • Note learning on fretboard
  • Customizable scale learning
  • Arpeggio visualization
  • Song progression analysis
  • Music theory education
Features
Read full description

Quinn Fetrow's Guitar Machines is a free tool to help teach you basic music theory concepts on guitar! I've got 4 guitar machines for you: 1. Note Machine - Teaches the notes on the fretboard one at a time, with options for randomization! 2. Scale Machine - Learn whatever scales you want in context of the CAGED system or use the "Custom Cage" setting to generate scales within a range on the fretboard. 3. Arpeggio Machine - Learn the arpeggios through the circle of fifths, or create your own arpeggio by selecting the notes of the chord. 4. Song Machine - Visualize the arpeggios of a song as it plays through its progression. I want you to learn how to play guitar!

About

OpenString

This app provides essential tools for guitarists, including a tuner, metronome, chord handbook, and a personal songbook. It offers all features upfront with no subscriptions or in-app purchases, allowing users to manage their own song charts and practice effectively offline.

Highlights
  • Guitar tuner
  • Metronome with tempo and meter settings
  • Chord handbook with fingerings and voicings
  • Personal songbook for lyrics and chords
  • Key transposition and capo preference
  • Scale and shape finder
Features
Read full description

Every guitar practice tool is included: tuner, metronome, chord handbook, and a personal songbook. No subscription, no account, and no catalog paywall. OpenString is built for guitarists who want the tools on their phone, not a rented song library. Install it from the App Store. You get the tuner, metronome, chords, and songbook. There is nothing left to unlock later. WHAT YOU GET Guitar tuner Tune a standard six-string guitar with the microphone. Choose a preset, let the app pick the string or choose it yourself, and play a reference note when you want a target pitch. Audio is processed on your iPhone. It is never recorded or uploaded. Metronome Keep time from 40 to 240 BPM. Tap a tempo, set the meter, choose subdivisions and accents, run a practice timer, or mute the click and follow the beat visually. Chord handbook Look up common major, minor, and seventh fingerings in standard guitar tuning. Search the handbook, save favorites, hear a reference voicing, and jump to alternate positions on the neck. Personal songbook Keep your own lyrics and chords. Transpose the displayed key and save a capo preference without rewriting the source chart. Add song metadata, build named setlists, practice with autoscroll, jump to chords used in a song, and import ChordPro. Create and edit on your phone, then export a backup to a destination you choose and restore it later. Song to chords Pick a song and get its chords and words together in one tap, ready to play and sing. Scale and shape finder Type a scale like A minor pentatonic and see its box shapes on the neck, with the fret positions you actually play them in. HOW THIS IS DIFFERENT There are no in-app purchases and no subscription. Every current tool is included with the app. The tuner, metronome, chord handbook, and songbook are not split across plans. No commercial song catalog is included. Your songbook is filled by you, whether you type it or import ChordPro. That is the point: your charts, your lyrics, your practice. The app works offline and needs no account. No feed. No ads in the app. WHO IT IS FOR Players who want a tuner, metronome, chord diagrams, and their own charts in one place. People who write songs, type lyrics and chords they already play, or import ChordPro. WHO IT IS NOT FOR OpenString does not rent you a library of popular songs or official tabs. If you want a commercial catalog behind a monthly plan, this is not that app. OpenString is built for guitar practice on iPhone.

Screenshots

Guitar Machines!4 screens
OpenString4 screens

Verdict

The call

The clearest difference is in-app purchases: Guitar Machines! at none against OpenString's 1. Guitar Machines! also leads on ratings volume (43 vs 1). OpenString's advantage is update cadence (daily vs every 3 weeks). On price, rating, review sentiment and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. OpenString sells 1 one-off in-app purchase. Guitar Machines! asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for Guitar Machines! against 5.0 for OpenString. That said, the two scores are not equally well evidenced: Guitar Machines! has 43 ratings behind it against 1, so its average is the more settled of the two. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

Guitar Machines! ships an update every 3 weeks, OpenString daily. The most recent releases landed on October 31, 2026 and October 24, 2026 respectively.

Scorecard3 real differences · 7 level
Guitar Machines! versus OpenString: the parameters behind the verdict, then further details
ParameterGuitar Machines!OpenString
PriceFreeFree
Rating5.0 (43 ratings)5.0 (1 ratings) — better
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings43 — better1
Update frequencyEvery 3 weeksDaily — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFreeFree
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.115.1
Further details — not scored
Size32 MB47 MB
Age rating4+4+
DeveloperQuinn FetrowTechguyver Labs, LLC

Customer experience

Guitar Machines!

All ratings25 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews22 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

OpenString

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Guitar Machines!

No in-app purchases

1 purchases

OpenString

One-time1
  • OpenString Pro$9.99

Questions

Is Guitar Machines! free?
Guitar Machines! is free to download, with no in-app purchases.
Is OpenString free?
OpenString is free to download, with in-app purchases available.
Which has better reviews, Guitar Machines! or OpenString?
OpenString is rated higher. Guitar Machines! averages 5.0 out of 5 from 43 ratings, while OpenString averages 5.0 from 1 ratings.
Do Guitar Machines! or OpenString have ads?
Neither Guitar Machines! nor OpenString shows ads.
Which is updated more often, Guitar Machines! or OpenString?
Guitar Machines! ships an update every 3 weeks, and OpenString daily. Most recently, Guitar Machines! was updated on October 31, 2026 and OpenString on October 24, 2026.

Other comparisons