Symbol-based AAC apps use pictures, icons, or pictograms to represent words. The user taps symbols to build sentences, and the app speaks them aloud. This approach is the most common form of high-tech AAC, and there are more options available today than ever before.
This guide compares the major symbol-based AAC apps, explains what makes each one different, and helps you figure out which might work for your situation.
What Makes an App "Symbol-Based"?
AAC apps generally fall into two categories:
Symbol-based apps display visual representations (pictures, icons, pictograms) of words and concepts. The user communicates by selecting symbols. These apps are designed for people who may not read text fluently, including young children, people with intellectual disabilities, and early communicators.
Text-based apps provide a keyboard for typing words. The app then speaks the typed text aloud. These are designed for people who can read and spell but can't produce speech. Some text-to-speech apps for kids add word prediction and phrase banking.
Many modern apps blur this line. A symbol-based app might include a text keyboard for literate users. A text-based app might include some picture buttons for quick phrases. But the core design philosophy is usually one or the other.
This guide focuses on symbol-based apps, since they serve the largest group of AAC users.
Major Symbol Sets Explained
Before comparing apps, it helps to understand the symbol sets they use. Each app is tied to a specific symbol library, and switching later isn't always easy.
PCS (Picture Communication Symbols)
Created by Tobii Dynavox. The most widely used symbol set in clinical settings, with 45,000+ symbols. Consistent line-drawing style with color fills. If your child has used Boardmaker materials in therapy, they've seen PCS symbols. Used in TouchChat and TD Snap.
SymbolStix
Developed by n2y. Features a distinctive stick-figure style that some users find cleaner and easier to distinguish than PCS. About 30,000+ symbols. Used in AssistiveWare's Proloquo products.
Mulberry Symbols
An open-source set with around 3,500 symbols. Simple line drawings designed to be clear at small sizes. Free to use and distribute. Growing, but the vocabulary coverage is smaller than commercial sets.
OpenMoji
An open-source emoji-style symbol set. Roughly 4,000 symbols following the visual language of smartphone emojis. Familiar to children who've grown up with messaging apps.
ARASAAC
Created by the Aragonese Centre for AAC in Spain. Over 12,000 pictograms, available for free under Creative Commons. Widely used in Europe and Latin America. Supported by LetMeTalk and several other free apps.
Tawasol
Developed specifically for Arabic-speaking users. Around 1,000 symbols with culturally appropriate representations for food, clothing, religion, and social customs. Fills an important gap that Western symbol sets don't address.
How Grid Layouts Work
Every symbol-based app uses a grid. Understanding grid design helps you evaluate apps effectively.
Grid size
Grid size determines how many symbols appear on screen at once. Common sizes:
- 2x2 to 3x3 (4 to 9 buttons). For beginning communicators. Large targets, easy to scan visually, but very limited vocabulary per page.
- 4x4 to 5x5 (16 to 25 buttons). A common middle ground. Enough vocabulary to be useful, targets still large enough for most motor abilities.
- 6x6 to 8x8 (36 to 64 buttons). For experienced users. Fast access to large vocabulary, but requires good visual scanning and motor precision.
- 10x10+ (100+ buttons). For highly proficient users. Maximum vocabulary density.
Most AAC apps let you adjust grid size. This is important because the right size changes as the user develops skills. An app that locks you into one grid size will be outgrown.
Navigation depth
No grid can hold every word. Apps use folders (sometimes called pages or categories) to organize additional vocabulary. The key question is: how many taps does it take to reach a given word?
- 1 tap. Core words visible on the home screen. Fastest access.
- 2 taps. Open a category folder, then select the word. Reasonable for common vocabulary.
- 3+ taps. Navigate through multiple folder levels. Slow. Frustrating for users.
Good apps minimize navigation depth by keeping high-frequency words on the main screen and organizing category folders efficiently.
Motor planning
When a word always lives in the same location (same grid position, same navigation path), the user develops muscle memory. Over time, they stop searching and start reaching automatically. This is motor planning, and it's one of the most important factors in AAC efficiency.
Apps that rearrange buttons, change layouts between grid sizes, or move words around undermine motor planning. Look for apps that maintain consistent word placement.
The Major Symbol-Based AAC Apps
SabiKo
Platform: iOS and Android Symbol set: Custom library (8,400+ symbols) Price: Free tier (permanent), Pro at $29.99/year or $79.99 lifetime Best for: Families who want a full-featured app without high upfront costs
SabiKo is our app. We're upfront about that. Here's what it offers.
The free tier includes 200+ core words, 8,400+ symbols, 6 neural voices, full board editing, word prediction, grammar correction, visual schedule, visual timer, choice maker, communication passport with PDF export, cloud sync, and full offline support. That's not a trial. It's a permanent free tier.
Pro adds all 37 voices across 5 languages (English, Spanish, French, German, Portuguese), up to 10 profiles, usage stats with PDF/CSV export, sound board, draw board, print board, custom audio, vocabulary packs, custom grid layouts, and a high contrast theme.
The main limitation is symbol library size. At 8,400+, it covers everyday communication well but has less depth than PCS (45,000+) in specialized vocabulary.
Proloquo2Go
Platform: iOS only Symbol set: SymbolStix (30,000+) Price: $249.99 (one-time purchase) Best for: iOS families who want a clinically established app with deep vocabulary
Proloquo2Go has been the standard recommendation in many SLP practices for years. It uses a Crescendo vocabulary system that grows with the user, from 7 buttons up to a full grid. SymbolStix symbols are clean and distinctive. The app has thorough vocabulary organization and strong clinical documentation support.
The price is the biggest barrier. At $249.99, it's a significant investment. There's no free tier, though a limited trial is available. iOS only, so Android families are excluded.
Proloquo
Platform: iOS only Symbol set: SymbolStix Price: $99.99 (one-time purchase) Best for: Newer AAC users on iOS who want a simpler AssistiveWare product
Proloquo (without the "2Go") is AssistiveWare's newer, simplified app. It has a cleaner interface than Proloquo2Go and is designed to be easier to set up. Lower price point at $99.99. Still iOS only and still a significant cost.
TouchChat HD
Platform: iOS only Symbol set: PCS or SymbolStix (user chooses) Price: $149.99 to $299.99 Best for: Clinicians and families already using PCS in therapy
TouchChat offers multiple vocabulary page sets designed by AAC professionals. The ability to use PCS symbols is a differentiator, since many therapy materials use PCS. WordPower page sets are well-regarded in clinical settings. Multiple grid sizes and customization options.
The price is high, and the interface can feel complex for new users. iOS only. The learning curve for setup is steeper than most competitors.
TD Snap
Platform: iOS, Android, Windows Symbol set: PCS (45,000+) Price: $0 to $299/year (subscription tiers) Best for: Users on Tobii Dynavox hardware, or those who need PCS symbols on a mainstream tablet
TD Snap is Tobii Dynavox's flagship software. It offers the largest PCS symbol library (45,000+) and integrates with Tobii Dynavox hardware like the TD I-Series. Available on multiple platforms, which is uncommon for premium AAC apps.
The subscription pricing model means ongoing annual costs rather than a one-time purchase. The app is powerful but complex, and full functionality often requires clinical support for setup.
LAMP Words for Life
Platform: iOS only Symbol set: PCS-based (Unity vocabulary) Price: $299.99 Best for: Users following the LAMP (Language Acquisition through Motor Planning) approach
LAMP Words for Life is built around the LAMP methodology, which emphasizes consistent motor patterns. Every word always requires the same sequence of button presses, regardless of context. This makes motor planning highly efficient over time.
The app is specifically designed for the LAMP approach, so it works best when paired with LAMP therapy. It's not a general-purpose AAC app. The price is the highest on this list, and it's iOS only.
Comparison Table
| Feature | SabiKo | Proloquo2Go | TouchChat | TD Snap | LAMP WFL |
|---|---|---|---|---|---|
| Platform | iOS, Android | iOS | iOS | iOS, Android, Windows | iOS |
| Price | Free / $29.99/yr | $249.99 | $149.99 to $299.99 | $0 to $299/yr | $299.99 |
| Symbols | 8,400+ | 30,000+ (SymbolStix) | 45,000+ (PCS) | 45,000+ (PCS) | PCS-based |
| Free tier | Yes (full features) | No (trial only) | No | Limited free | No |
| Voices (free) | 6 neural | N/A | N/A | Limited | N/A |
| Voices (total) | 37 | Multiple | Multiple | Multiple | Multiple |
| Offline | Yes | Yes | Yes | Yes | Yes |
| Languages | 5 | 18 | Multiple | Multiple | English focus |
| Grid customization | Yes | Yes | Yes | Yes | Fixed (motor planning) |
| Grammar support | Yes | Yes | Limited | Yes | Limited |
| Data tracking | Pro | Yes | Limited | Yes | Limited |
Key Differentiators
What actually separates these apps? Features lists look similar. Here's what matters in practice.
Cost structure
This is the sharpest divide. SabiKo offers a permanent free tier with real functionality. Every other symbol-based AAC app either requires a large upfront payment ($100 to $300) or a subscription ($99 to $299/year). For families on a budget, this is often the deciding factor.
Platform availability
If you use Android, your options narrow significantly. SabiKo and TD Snap support Android. Proloquo2Go, TouchChat, and LAMP are iOS only. This single factor eliminates half the market for Android families.
Symbol familiarity
If your child already uses PCS symbols in therapy (common if they've used Boardmaker materials), TouchChat or TD Snap provide continuity. If they've used SymbolStix, Proloquo apps are the match. SabiKo uses its own symbol library, which means some visual adjustment.
Clinical integration
Proloquo2Go and TouchChat have the longest clinical track records. Many SLPs are trained on these apps and have ready-made therapy materials for them. If your SLP strongly recommends a specific app, their expertise with that tool has value.
Motor planning approach
LAMP Words for Life is unique in its commitment to consistent motor sequences. If your child's therapy follows the LAMP methodology, this app is designed for that approach. No other app replicates it as faithfully.
Who Each App Is Best For
SabiKo. Families who want a capable AAC app without spending hundreds of dollars. Android users. Families who need multilingual support (English, Spanish, French, German, Portuguese). First-time AAC users who want to try a full-featured app at no risk.
Proloquo2Go. iOS families with budget for a premium app. Users who need access to 18+ languages. Families working with SLPs trained on Proloquo products.
TouchChat. Users already familiar with PCS symbols from therapy. Clinicians who want WordPower page sets. Families who need PCS consistency between therapy materials and the AAC device.
TD Snap. Users on Tobii Dynavox hardware. Organizations that want enterprise-level AAC across multiple platforms. Users who need the deepest PCS vocabulary (45,000+ symbols).
LAMP Words for Life. Users in LAMP therapy programs. Individuals where motor planning consistency is the top priority. Families committed to a motor-based AAC approach.
How to Choose
Here's a decision framework.
- What platform do you use? If Android, focus on SabiKo or TD Snap. If iOS, all options are available.
- What's your budget? If $0, SabiKo is the clear choice. If $100 to $300 is feasible, consider all options.
- What symbol set does your child already know? Match the app to existing familiarity.
- What does your SLP recommend? Their clinical experience with specific apps matters.
- Does your child need a specific therapy approach (like LAMP)? Choose the app built for it.
- What languages do you need? Check language support before committing.
Download one or two options. Use them for a few weeks each. Involve your SLP. The right app is the one your child will actually use every day. For a broader comparison that includes free and text-based options, see our best AAC apps for kids roundup.
Download SabiKo free and start exploring symbol-based AAC today.