So this is why the 62 was being so deeply discounted recently: Major updates: iPhone connectivity Rechargeable or AA battery system Glonass More internal memory Introducing the GPSMAP 64 Series Updating Popular Outdoor Handheld Click the title above to go to the site for more information. "The GPSMAP 64 series boasts a 2.6-inch sunlight-readable transflective color display and a high-sensitivity GPS and GLONASS receiver with a quad helix antenna for superior reception. With the addition of GLONASS satellites, the time it takes for the receiver to lock on to a position is (on average) approximately 20 percent faster than using GPS alone. This allows users to get their position quickly and precisely even in heavy cover and deep canyon. Additionally, the 64s adds wireless connectivity for data transfer between other compatible Garmin handhelds and mobile apps, and for Smart Notification technology. With this, users can receive emails, texts and alerts right on the device (when paired with an iPhone 4S and later). This allows users smartphones to be safely protected from the elements. " "All of the devices in the GPSMAP 64 series have a unique dual-battery system, where both standard AA batteries and a rechargeable NiMH battery pack (sold separately) can be used. Plus, all of the GPSMAP 64 devices have internal memory (4GB for 64/64s and 8GB for 64st), and a microSD card slot to store additional data and maps. " I have no idea yet if they've improved the electrical connection or are relying on mini-usb.