Elaborated answers to your questions:

Are you still collaborating with UNICEF + the Burundi Innovation Lab?
 No. but we could likely re-engage them with this project if we have a clear plan of action (like a business plan) that includes details for short- and long-term project execution and development

Did they gather feedback + input from locals on the ground that you could share?
We've looked through my notes and there isn't a lot of direct feedback about or from the end user. The closest I can get is to say that the problem of affording to charge your phone is real in rural Burundi. Chelsey and Alfred ( from Innovation Lab Burundi) made it clear to us that this is a consistent issue, that people spend roughly 25% of their income to charge their phones and have to go to great lengths (sending the phone away to charging stations in bigger cities) and that brining the cost down and accessible charging closer would be impactful.

We also see an attempt at doing this in other projects - namely Lumiere - from which we can draw the conclusion that this is something helpful to communities. One way Chelsey was specifically helpful was in finding out costs of things (how much people pay for charging where, cost to get the components to charge your own phone, etc) so we know our business evaluation numbers are solid. The question of how well (or not) people would react to using the solidarity groups to accomplish these goals is somewhat unknown.

... I am curious to know if you also developed the product for charging?
We did not. In fact, we deliberately chose not to develop a new product since there are existing products that use different methods (solar, car batteries, etc) to create portable charging stations. The problem is not that a portable charger doesn't exist, it's a problem of distribution/accessibility, affordability, control, and longevity. Our project integrates existing systems and products to create a new system (business model) that is more beneficial to the participants and sustainable and addresses these aforementioned issues.

Do you have in mind other partners to take this idea forward?
We can draw here from our long list of similar projects/programs. Maybe: Angaza / Fenix Power Systems (charging station product), UNICEF Innovation Lab (on-the-ground support/monitoring), Solar Sister / Living Goods / Grameen Shakti (micro-entrepreneurship & teaching/training), LEO (mobile money), U-Com (Burundi telecom responsible for LEO), Burundi Business Incubator (BBIN)

Is there any feedback or support that you are currently in need of?
I think one of the first things we'd need is to get in touch with solidarity groups to find out if this is something they'd be interested in. Once we get buy-in from them, the rest is figured out (or at least at a place where it can be piloted).

How are you planning to prototype this idea in the short term?
In order to prototype this, we'd have to get our hands on the mobile charging station that we want to use and develop the content of any training/informational materials. The system of deployment and feedback is thought through. Is there a way to prototype this in a place closer to home, I wonder?

Thanks Meena and Lusia for appreciating our idea :)

Following are the answers to your questions.
1. This was the idea we developed for UNICEF last semester and we never revisited it after December.

2. We got a lot of feedback from local Burundi Innovation Lab while we were working on the idea. The current project is the out growth of that feedback.

3. We were going to use the existing solar charging kits available in the market.
During our research we found that most of the burundians commute using bicycles, in that case access to car battery might be difficult (to carry it around etc.). Plus our business model might not work with car batteries, as it won't be profitable.

We would love to work or share our experience and research with any NGO (dealing in micro finance ) who can be our feet on the ground.

4. I think the idea is quite flexible and I can see its being implemented in India too.

Thanks :)