Jellow is a communicator that uses icons/images to enable speech. It can be used by those learning to speak or those having difficulty with speech.

Jellow is developed at the IDC School of Design at the Indian Institute of Technology Bombay located in Mumbai.

A novel Visual Emotional Language Protocol (VELP) was conceived in order to enhance the language ability of Jellow. VELP represents the 6 core expressive icons of the interface. Using these core buttons, the child can communicate their likes, dislikes, and needs with others.

Jellow has an easy-to-learn interface and visually appealing icons. It is currently available in English and Hindi. The application is still under development. If you have any suggestions for improvement, please submit your feedback/comments below.

Jellow application is optimized for Android tablets.

Jellow is freely available for download here

Download 'JELLOW' App

Frequently Asked Questions

  • What are the best devices for Jellow?
    Jellow has been optimized for tablets. Although it also works on mobile phones, we are still working on optimizing it for mobiles of different screen sizes.

  • What operating systems are compatible with Jellow?
    Jellow is developed for Android devices with Android versions 4.0 and above. Jellow is currently not available for iOS and Windows platforms. Please note that Jellow will not run on desktops or laptops.

  • What is the price of Jellow?
    Jellow can be downloaded for free on Google Play using the link -

  • Can Jellow run offline?
    Jellow can run offline on your device. An Internet connection is only required at the time of download of the application for the purpose of registration.

  • How do I use Jellow?
    Jellow is a communication aid for people learning to speak or with difficulty in speech. To speak using Jellow, simply click on any of the central category buttons followed by any of the expressive side-buttons. For more details regarding the use of the application, please visit the "Tutorial" page by clicking on the top right corner of the application.

  • Jellow's voice and pronunciation of words is not clear. What do I do?
    The application uses the Google Text-to-speech (tts) engine. Most devices already have the Google tts engine activated. However, on all Samsung devices, the Samsung tts engine is activated by default. To obtain the best results while using Jellow, the user will need to activate the Google tts engine by going into the "Language and input" option within the "Settings" of their device. The user will then need to download the Hindi (India) voice by going into settings of the Google tts engine. In case the device does not have the Google tts engine, it can be downloaded for free from Google play using the link -

  • What languages are available in Jellow? How do I change the language output of Jellow?
    Currently, the application is available in English and Hindi. You can change the language output of Jellow by going to the "Settings" page by clicking on the top right corner of the application. You can also play around with the speech speed and the voice pitch on this page.

  • How do I get Jellow to speak content not included in the core vocabulary of the application?
    We have provided a "Keyboard" button at the bottom right side of the application that enables the user to type out custom sentences that can then be spoken by clicking on the speaker button within the application.

  • Why should I create my child's user profile in Jellow?
    The application allows you to store your basic contact information including your address, your contact number, your email address, as well as your child's blood group. In case of an emergency involving your child in your absence, medical/paramedical staff can contact you by accessing this information. This information can be accessed by clicking on the "About me" sub-category button (under "Help") and each of the expressive side-buttons. Your child's profile information can be updated on the "Profile" page accessed by clicking on the top right corner of the application.

  • Does Jellow remember my child's choices?
    Jellow uses a preference algorithm to keep track of the user's "most-used/preferred" icons and displays these options as the top choices on the screen. However, you can restore the original order of the icons using the "reset preferences" option by clicking on the top right corner of the application.

  • How do I provide feedback to the Jellow developers through the application?
    You can access the "Feedback" portal by clicking on the top right corner of the application. You can rate the application on several parameters and also provide suggestions and comments through this portal. When you click on the "Submit" button you will be prompted to choose an email client through which this feedback can be sent to the Jellow team. You will need an Internet connection to provide feedback to the developers.

  • What is unique in Jellow compared to other AAC devices/applications?
    A novel and unique Visual Emotional Language Protocol (VELP) consisting of the 6 expressive side-buttons was conceived for Jellow. Significant efforts have also been dedicated to customizing the content of Jellow to the socio-cultural context of India. Another unique feature in Jellow that is currently not available on any other AAC app is its ability to teach children the sequential steps of daily activities such as brushing, going to the toilet, and bathing. Jellow has a child-friendly step-by-step pictorial depiction of each of these activities of daily living so that kids can follow along as they learn to perform these critical skills.


Team Members:

  • Project Investigation, Conception, and Supervision:
    Prof. Ravi Poovaiah and Dr. Ajanta Sen
  • Initial Concept Development:
    Anchal Kumar, Samraat Sardesai, Peter Joseph, Antara Hazarika
  • Software development:
    Sumeet Agrawal, Roop Sahoo, Shruti Gupta, Yogesh Masaye, Dhairya Dand, Pritam Pebam
  • Website design:
    Prof. Ravi Poovaiah, Yogesh Masaye, Sumedh Garud, Roop Sahoo
  • Icons and visual design:
    Vinaya Tawde, Anisha Malhotra, Nikita Iyer, Ganesh Gajjela, Sumedh Garud
  • Translation:
    Sachin Sonawane, Dr. Sudha Srinivasan
  • Research, vocabulary development, and user studies:
    Dr. Sudha Srinivasan
  • Support:
    E-kalpa project sponsored under NMEICT by MHRD and Microsoft Design Expo 2004


  • Dear visitor, if you have queries, suggestions, and comments about 'JELLOW' or need more detailed information about the project, please contact us at our following office address or please fill up the form and we will get back to you at the earliest.

    Your opinion and feedback will be appreciated.

    Postal Address:

    Project Jellow
    IDC School of Design
    IIT Bombay
    Mumbai - 4000 076
    Phone: 091-22-25767820/4815/4827
    email: dsource.in[at]gmail.com