I use the
Holux M1200. It is SUPER TINY and has an awesome battery life. The website claims 16 hour use, but I have had up to 20 hours.
Features
‧ Built in MTK MT3318 Low power consumption GPS chipset.
‧ 32 parallel satellite-tracking channels for fast acquisition and reacquisition.
‧ Superior sensitivity up to -159 dBm.
‧ Built-in WAAS/EGNOS Demodulator without any additional hardware. Or use the high-sensitive software to get the fast acquisition and reacquisition in the urban, canyon and foliage environments.
‧ Compatible with Bluetooth Serial Port Profile (SPP) completely.
‧ Low power consumption. Built-in rechargeable and changeable Lithium-ion battery, the working time can last 15 hours maximum.
‧ Provide expand terminal contact to other system without Bluetooth device.
‧ Support NMEA0183 V 3.01 data protocol
‧ 3 color-LEDs indicate to show the status of device.
‧ FLASH based program memory. New software revisions upgradeable through serial interface
‧ Small, sleek, and lightweight design easily fits in your hand.
‧ Over-Temperature protection
‧ Enhanced algorithms -SnapLock and SnapStart provide superior navigation, performance in urban, canyon and foliage environments.
‧ For Car navigation, Marine navigation, Fleet management, AVL, Personal navigation, Tracking System, and Mapping device application.