There was a post in the AAC for SLP Facebook group today where a member asked the following question:
“Hi all! I’m not sure there is even an answer for this question, but I’m going to go for it anyway. 
Is there one symbol set that is most widely used? I am only familiar with SymbolStix and PCS. To be specific, I’m not looking for people’s preferences… I am truly just interested on any data/study that demonstrate(s) which is most widely used.
“
I hadn’t ever seen a list or data/study that had this exact info. To truly know which symbol set is most widely used for high tech AAC you’d need to have data regarding sales of SGDs, sales of AAC apps, sales of symbol sets via in-app purchases and data regarding their actual use. My guess is this is going to vary greatly across the world and influenced by both the language(s) needed by a particular AAC user and the opinions of SLPs / SLTs about certain apps or SGDs.
To truly know which symbol set is most widely used for paper-based AAC you’d need to have data regarding sales and subscriptions and then a way to determine actual use for AAC vs. all the other possible uses for those symbols.
See this separate post for info about Apps & Websites to Create Materials with Symbols: https://omazingkidsllc.com/2020/08/25/apps-websites-to-create-materials-with-symbols-on-an-ipad-iphone-list-compiled-by-angela-moorad-ms-ccc-slp-at-omazing-kids/
But it sparked my curiosity about what symbol sets are either included or available via in-app purchase in iOS AAC apps. So I looked through my vast AAC app collection and came up with the following list of symbol sets.
Based on the data that I collected, SymbolStix appears to be the most widely used (used in the most apps, available in 7 of the top 10 iOS symbol-based AAC apps – denoted by (*) in the lists below & available in traditional SGDs)
PCS symbols are commonly used (available in 6 of the top 10 iOS symbol-based AAC apps – denoted by (*) in the lists below). Especially if you factor in paper-based AAC systems like PODD and their use in traditional SGDs)
Widgit is more commonly used in the UK than the USA (available in 3 of the top 10 iOS symbol-based AAC apps – denoted by (*) in the lists below & traditional SGDs)
Minspeak symbols (and the closely associated symbols used in LAMP Words for Life) are only used in particular SGDs and that app but those are widely used.
More info about the Top 10 iOS Symbol-Based AAC apps: https://omazingkidsllc.com/2021/02/18/top-10-ios-symbol-based-aac-app-feature-matching-chart-compiled-by-angela-moorad-ms-ccc-slp-omazing-kids-aac-consulting/
My Data:
SymbolStix:
1. aacorn+
2. Alexicom
3. Avaz (*)
4. Bridge Communication
5. Clicker Communicator (*)
6. CoughDrop (can add-on) (*)
7. GoTalk Now / GoTalk Now Plus (*)
8. Grid 3 on SmartBox SGDs (also available on other SGDs)
9. Grid for iPad (*)
10. Grid Player
11. Proloquo2Go (*)
12. simPODD
13. So Much 2 Say
14. Sono Flex
15. Talk Tablet
16. TouchChat with WordPower (*), also available on Saltillo SGDs
PCS:
1. Chatable
2. Clicker Communicator (*)
3. CoughDrop (can add-on) (*)
4. GoTalk Now (as in-app purchase) (*)
5. Grid 3 on SmartBox SGDs (also available on other SGDs)
6. Grid for iPad (*)
7. Snap Core First (also available on Windows devices and Tobii Dynavox SGDs) (*)
8. TouchChat with WordPower (as in-app purchase) (*), also available on Saltillo SGDs
Widgit:
1. Clicker Communicator (*)
2. GoTalk Now / GoTalk Now Plus (as in-app purchase) (*)
3. Grid 3 on SmartBox SGDs (also available on other SGDs)
4. Grid for iPad (*)
Open Source Symbols (most available on this website: https://www.opensymbols.org):
1. Cboard
2. ChatterBoards
3. CommBoards
4. CoughDrop (*)
5. ElineSpeaks
6. Leeloo
7. LetMeTalk
8. MyTalk
9. PhotoVOCA
10. Posco
11. SpeakProse (emojis)
12. SymboTalk
CrickPix:
1. Clicker Communicator (*)
GoTalk Image Library:
1. GoTalk Now / GoTalk Now Plus (*)
LessonPix:
1. CoughDrop (*) (can sync with your LessonPix account).
LessonPix is also widely used to make printed AAC options.
MetaCom (used fairly frequently in Germany)
1. GoTalk Now / GoTalk Now Plus (as in-app purchase) (*)
2. MetaTalkUS
3. Snap Core First (as in-app purchase) (*)
Minspeak:
1. Unity on Accent SGDs
Multi-Meaning symbols derived from Minspeak & Unity:
1. LAMP Words for Life (*), also on Accent SGDs
Persona:
1. Talk Suite Pro
Pics for PECS:
1. PECS IV+
Pixon (also related to Minspeak/ Unity):
1. TouchChat with WordPower (as in-app purchase) (*), also available on Saltillo SGDs
Smarty Symbols:
1. ASD AAC Bestie Communicator
2. Expressive
3. Speak for Yourself (*)
4. Quick Talk AAC
Smarty Symbols are also widely used to make printed AAC options, in products on Teachers Pay Teachers and in a few non-AAC apps.
There are other AAC apps and SGDs that have their own unique symbols:
1. CardTalk
2. CoreVoice
3. EESpeech
4. Fluent AAC
5. Grace 4
6. Lingraphica (apps and their SGDs)
7. My First AAC
8. Niki Talk
9. PAROL Mini
10. PictoMaker
11. SoundingBoard
12. Talking Mats
13. Talk to Me
14. Top Taps Speaks
15. Verbal Me
16. Visuals2Go
17. Voice4u
18. Wayword
This website has a nice catalog of all (or at least most) of the various symbol sets. Most are not widely used. I think it’s interesting to read the history behind how/why symbols were developed: https://talksense.weebly.com/symbol-what.html
It’s important to keep in mind… Symbol sets are like any other feature in AAC. There isn’t any “one size fits all” and to my knowledge there isn’t any research supporting the idea that any particular symbol set is superior to another. This is especially true when considering symbols that meet specific needs, user preferences, culturally relevant, etc…
See this quote from PrAACtical AAC: “There is no empirical evidence that one type of symbol is superior to another for all AAC clients, but there may certainly be differences for a specific individual. That’s why it is a best practice to evaluate the kind of symbol to use as part of an AAC assessment rather than picking one at random or using one based on our own convenience.”
And this post from NWACS:
https://www.nwacs.info/blog/2019/3/aac-and-symbol-selection
The best way to reach me with any questions is via messaging on the OMazing Kids Facebook page: https://www.facebook.com/OMazingKidsAAC/. That way AAC related messages don’t get lost among the spam in my e-mail
Angela Moorad, MS, CCC-SLP, Founder of OMazing Kids, LLC OMazing Kids AAC Consulting
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