Android phones with built-in GPS | accelerometer | digital compass make it apt for outdoor activities including bicycling, especially the weather-proof ones. Add that with many applications available to utilize these features e.g.: maps, speedometer/odometer, shock-meter - you'll have a very bike-friendly gadget.
Mount an Android phone securely to your bike is what we'll discuss here. This is how I mount Samsung Galaxy 5 (GT-i5503) on my Polygon Premier.
Tool :
Material :
- unused Kyocera belt-clip
- mouse pad
- band with Velcro
How to install :
Kyocera belt-clip has a matching wide size, but too deep, so I had to insert cut mouse pad between the belt-clip and the phone and that makes Samsung Galaxy 5 locked inside the belt-clip. It already has a clip so it was easy to attach it to stem with a Velcro-ed band .
You can use another cut mouse pad between stem and belt clip to secure its position.To make it even secure, you can use rubber band from unused inner tube.
If you own a custom belt-clip specifically for your phone, it will be more secure.
Give it a try, on your own risk :)
Ready-to-use helmet light doesn't come cheap. Want to save some money and make your own?
AFAIK, helmet light cost more than 10 $, my home made helmet light cost me less than 8$, although actually it cost me nothing since I already have the items laying around my house. 
Materials :
- Energizer Headlight that comes with 3AAA batteries (~7 $), the advantages of this light are :
- swivel head to fine tune the light angle,
- two light modes : 2 white LEDs or 1 red LED,
- bright enough to light dark road (49 lux),
- claimed to last 50 hours - zip ties (less than 0.1 $)
Tools : nothing
Installation :
Very simple., just find the right spot on your helmet then fasten it with zip ties through helmet holes. You can cut the headlight rubber band, but if you don't want to, you can hide and fasten it with zip ties.
how to fasten headlight onto a helmet
white bright light mode
red night vision mode
I am satisfied with the result, and because of the light and antennae like zip ties, it looks like Power Ranger + Masked Rider helmet :)
Disadvantages of this home made helmet light :
- to replace batteries, zip ties must be cut, fortunately zip ties are cheap and it is not that frequent to replace batteries.
- not water resistant, although it depends on what kind of head light you use.
Before using on night ride, test it first to see if it fit your need or not. Have a safe night ride.
Use this tutorial on your own risk.
