As one of its daily deals, Best Buy offers the myCharge Sojourn 1,000mAh Battery Pack for iPhone or iPod touch, model no. RFAM-0194, for $19.99 with free shipping. That's the lowest total price we could find by $5. Sales tax is added where applicable. This external battery is designed for use with most non-Lightning Apple devices and purportedly powers up to four hours of talk time.

Also available is the myCharge Voyage 1,000mAh Battery Pack for Android, model no. RFAM-0206, for $19.99 wth free shipping. That's the lowest total price we could find by $5. It also provides four extra hours of talk time via your phone's microUSB port. Both deals end today.