1.5V to 5V DC-DC Convertor

I was looking for a simple solution for pumping 1.5 volts to 5 Volts. I have designed various 1.5v- 5V DC-DC Convertors by using special purpose chips. The problem was those chips are very difficult to obtain. Moreover, DC-DC Convertors are mostly required to use coil which is also difficult to get.

Luckily, I found this small breakout board in a local electronics shop (NPE). It was cheap, about USD 10 and small enough to fit in watch case (in the future).
The instruction is very simple, put 1.5 Volt in your will get 5V at the output.

By using this breakout board with my USB battery charger

Attaching this module to my digital wristwatch, then I have a working digital wristwatch. It can be charged via USB. Fully charged batter will make the watch lasts for 10-12 Hours (the display is always on). Now, it needs good case + strap. I have idea but don't have time to continue the project.

I have a plan to disclose the making process and give away the PCBs. But, there are some mistakes in the PCB. The problems can be resolved via firmware. However, I think it's not good to give away the incorrect PCBs. Please wait for the good PCBs and I'll give away some.