It all started with seeing a commercial for a hearing aid that has a phone app to control certain settings. It was similar to the Beltone Hearing Aids. This started me thinking about using smartphones to communicate with the deaf.
I have Bing Translator app on my phone which lets me translate a bunch of languages but I wondered if I could translate English to English. More specifically, if I could speak and the translator app would then show what I spoke as text. Yes, the translator app can do this. So if I find myself needing to communicate with a deaf person, I will be able to do so. Now, some people may say that using a note app can acheive the same thing by typing but the translator app can take my spoken word and translate it to any supported language. This will allow me to communicate to a deaf person no matter what language he/she understands.
Still being curisous about communicating with the deaf by using a smartphone, I searched the internet and came upon an app that is being developed by Transcense that allows the deaf to be involved in conversations with multiple people.
What about translating sign language? There doesn't seem to be phone apps just yet but there is research being performed in collabortation with Microsoft to use the Kinect to translate sign language to text. Phone cameras or Google Glass might be able to acheive the same goal of letting deaf people use sign language to communicate to anyone.
More internet searching lead me to Skype Translator which has been making headlines in the last year or so. Skype Translator can translate voice and instant messaging conversations in real time. On the FAQ page, there is a list of supported languages.
For instant messaging:
In that last list, Klingon is a supported language. I grew up watching the original Star Trek and now the Universal Translator is coming true.