The SoaPen team relies heavily on user feedback and takes it to heart. We work hard and smart to make ourselves easily understandable. How we've learned from our handwashing campaigns over the past year is visible quite clearly in the evolution of our print material, very specifically, the How To Handwash poster that has changed several times due to user feed back and the need of the hour.
The Original Yellow Poster
When we started laying out the website, we preferred to divide our content sections through creating color blocks. The How To Handwash section under looked clearest with a yellow background and worked well within the website but then we started conducting handwashing workshops in schools and realized that the poster wasn't print friendly. It wasn't just hard to read, it also used a lot of ink which was a big no-no in the fiscally conscious low income schools that we were conducting the workshops in.
The Print Poster
SoaPen activates with only a few drops of water. We noticed that when the students were using SoaPen, they would open the faucet fully and try to wash off the SoaPen marks without rubbing their hands fully. To combat that we specifically changed the second square depicting the 'wet your hands' motion to include only droplets of water and not gushing water like the previous poster. We also realized that instead of numbering the '7 steps of handwashing', it is visually clearer to have them be a separate section all together with a different color bounding box.
The Four-Step Poster 
A few schools had a very small time slot allotted to our handwashing campaign. We created a separate poster for our volunteers to show the class really quickly and handed the more elaborate poster to the class teacher to explain at her leisure. A critical addition to this poster was the depiction of the 'back of the hand' application as we noticed that the students were forgetting to do that even after being told to.
The Bilingual Poster 
The poster got a major revamp a few months after the last one as we moved to bilingual schools that had an equal number of hindi and english speaking students. We added hindi descriptions to reach as many students as we possibly could. We also elaborated on marking the back of the hand aspect and showed that the rubbing of the hands will slowly remove the SoaPen markings.
The Poster (as of now) 
Since the product had the circular illustrations, we decided to switch to those to maintain uniformity and increase familiarity. Cheers to always iterating to suit the users' needs!! :)