### Now includes Spanish too! ### The foundational resource and toolbox that demystifies every chord and makes learning a pleasure. Finally make sense of guitar chords!
Oolimo – The Guitar Chord Bible
Learn, understand and master guitar chords like never before.
Oolimo is the interactive learning and reference app that helps you finally make sense of chord symbols, chord names, and harmonic relationships on the guitar. Created by guitarist and developer Oliver Mochmann, Oolimo unites musical depth with clarity and usability—turning theory into something you can actually see, hear, and understand.
Why Oolimo is different?
The web is full of chord charts and tutorials—but few explain why chords work the way they do.
Oolimo fills this gap with a structured, unified, and accurate approach to chord theory. Think of it as a “foundational work” for guitar harmony—clear like a math framework, but engaging like a creative playground. Whether you’re a beginner or an experienced player, you’ll gain lasting insight instead of fragmented tips.
Main modules:
Chord Finder
Discover chords that really make musical sense. All shapes come from a manually curated database of usable voicings, transposed intelligently by an algorithm that knows real-world theory. Each chord adapts automatically to your selected key. Transfer shapes to the Analyzer with a single tap.
Chord Analyzer
Enter any fingering on the virtual fretboard and get the correct chord name instantly—no “unknown chord” messages. Supports standard and open tunings (chord analyzer only). Includes advanced notation options (slash chords, double accidentals, enharmonics) and shows all notes on the staff.
Chord Progressions
Explore, compare, and learn common and essential progressions with an innovative matrix that visualizes harmonic functions and relationships. Practice them in all keys and contexts.
Theory Lessons
22 interactive lessons including smart visalisations explain intervals, chord construction, voicings, slash chords, diatonic harmony, and every major chord type—from major, minor, and dominant 7 to altered, suspended, add, sixth, and diminished chords.
Quizzes
Test your knowledge and train your ear anywhere. The quizzes cover chord construction, intervals, harmonic context, chord types, voicings, tensions, and more—learning through play.
General features:
Interactive fretboard and chord diagrams with note and interval display
Playback of chords or single notes
Switchable between detailed or compact chord names
Day/night mode and left-handed mode
Languages: German, English, Spanish
This is the smartest tool I’ve ever seen not just in apps, but all across the internet, books, everything. The chord analyzer and chord finder sections compliment and work together fluidly and perfectly. The fact that you can click on strings and build chords that you may have played on the guitar and don’t know what they may be, or why they sound good to you, is a feature that even allows you to understand your own playing, and no tool or website can rival that. In addition, when looking up any chord in the list of chords, you can see it intelligently in every inversion, and you can also turn on arpeggio, and it’ll show the arpeggios relative to the chords your playing, and they are displayed slightly less prominently to the chord. That’s brilliant. It has saved me hundreds of hours of web searching and googling to answer simple questions. The visual design of this app is so simple, streamlined and genius, I don’t think anything rivals it. There’s also a button to sound any chord you create by selecting notes on the fretboard, and this app has even become something I can use to study music when I don’t have a guitar, like on an airplane. This app is so perfect, I honestly hope it never changes and is available for all foreseeable future. I’m blown away. I personally would count it as the best guitar app created to date, and possibly one of the greatest apps created of all time next to Shazam and Juxtaposer. It’s completely in a class of its own, there’s nothing to compare it to. If I had to, I would buy it 100x over. If you’re a guitarist you should have this immediately and it should be where mine is, on my first page of apps on my phone. To the designers and developers, a standing ovation. When I have new students, the first thing I do is make them buy this app, sometimes even before buying a guitar. This little app was birthed from pure brilliance.
Developer Response
Wow, I‘m speechless :-) Thanks for taking the time to write down all of this! This is super motivating. I will not rest on these laurels and carry on improving app and website (currently working on a bigger update of the latter). Kindest regards from Vienna, Oliver
The tool that teaches
SCRAP KING
Like other reviewers here, I used this online regularly and was thrilled to see it as a stand-alone app. It’s great because you can approach a chord from seeing/hearing inversions on the fly, or from forming your own and having its “tonal makeup” appear as you create it (where is the root, is there a lower 3rd or raised 5 etc) so it teaches you. In that regard you can go deep into the “description” field to really break out what’s happening. To top it off, the UX is one of my favorites, very intuitive and organized for the guitarist. My one gripe is that I could not get the app to show an 7aug or a m9b5? I think that probably falls into enharmonic equivalents, but I wish I could ask the developer what I’m missing?
Super impressed, excited to learn!
Justin Charles White
(Edited below)Extremely informative, great ui, and makes theory kinda fun! I’m always creating chords and wondering what they are and how they relate to each other, and this app helps me understand. My only request is for features of chord progressions to be added, as the web version already has. Other than that, amazing work!Edit: PLEASE add a chord library/option to save progressions to the app! Only 9 slots to save chords are available, but if we were able to save different progressions into folders to access later and/or save specific fingerings for chords we like, it would take this app to the next level!!!
BUY. THIS. APP. NOW.
Rokadome
I have been using the webpage Oolimo for years and have been waiting on the app for just as long. As a songwriter, it has helped me identify chords I “made up” or find chords I’ve been looking for. It is hands down the best application for guitar chords, bar none. There is so much I love about Oolimo that I can’t list it all here. The price for this app is an absolute steal and I would gladly pay 50 times the price for what this app can do. No question.If you play guitar, you NEED this app.
2.0.1
Fixed issues when the app was installed on desktop devices or MacBooks (not actually intended, but partially possible). Two things were adjusted:
Optimized audio code. The samples now use .wav files instead of .mp3.
Fixed problems distinguishing between touchscreen and mouse/touchpad input.
2.0.0
Spanish added — selectable for all users (alongside English and German).
Fresh icons on the start screen
Refined texts, improved explanations
Bug fixes and performance optimizations
Version 2.0.1
The developer, Oliver Mochmann, 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 Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Oliver Mochmann
Size
10.8 MB
Category
Education
Compatibility
Requires iOS 15.6 or later.
iPhone Requires iOS 15.6 or later.
iPad Requires iPadOS 15.6 or later.
iPod touch Requires iOS 15.6 or later.
Mac Requires macOS 12.5 or later and a Mac with Apple M1 chip or later.
