What are GSM national language shift tables?
The GSM national language shift tables are an extension to the GSM character set. They specify a number of extra pages in addition to the default GSM character set.
These extra pages are mostly setup for specific languages such as Turkish, Portuguese or Spanish. They also contain character sets such as Bengali, Hind, Urdu and many more.
It’s an important extension since it enables the use of these character sets without having to fall back to using Unicode. This means you can use up to 153 characters per message part as opposed to 70 when using Unicode.
You can find a complete list of characters in the GSM character set including national language shift tables here.
The only drawback of using national language shift tables verses Unicode: Only one character set and one shift table can be active per message part.
These languages are in the national language shift tables: