Let me talk about the OTG bit for a moment. Every knows about USB flash drives, or thumb drives. You connect them to a computer, and they appear like extra disks for storing files. The computer is the USB host, and the flash drive is the USB device.
OTG enables devices to reverse their roles. So, for example, while a smartphone or tablet is usually a USB device which connects to a USB host computer, the device can become a USB host and talk to other USB devices. Many Android smartphones support OTG functionality, enabling them to connect to other USB devices.
Physically, the USB OTG devices still use micro USB port. However, with a suitable OTG cable, one end has a micro USB B plug that connects to the USB OTG device, and the other end usually has a USB A socket, the standard kind you find on a computer. Into this socket, you can plug in any USB device.
The Sony Microvault USB Flash Drive for Smartphone, or USM-SA1, is a flash drive with the OTG connection built into it. On the one end is a standard USB A port which you can plug into a regular USB port on a computer, while on the other end, there is a micro USB B plug which connects into a smartphone or tablet that supports OTG.
The USM-SA1 is small and compact. I know that some USB storage gadgets can get even smaller, but I reckon this one is just the right size to not easily get lost.
There is a lockable rotating cap which covers the micro USB end of the USM-SA1. The cap is attached with a plastic strap, so it will not go missing. In addition, a strap hole on the cap lets you tie the USM-SA1 to your key chain or something else.
The USM-SA1 is still a regular flash drive, so you can just plug it into a computer and start using it. No need for drivers and such. On the OTG side, you just plug it into an OTG capable smartphone or tablet. Sony does provide a file manager app, which does not support Android 4.4. Instead, I used the Nexus Media Importer. (The app does cost a few dollars.)
I must stress that the OTG function is a feature of the smartphone or tablet. You need a gadget that supports OTG. Many new Android smartphones and tablets do, but be sure to check that out first.
Read/write speeds on the USM-SA1 is average. In the Blackmagic Disk Speed test, it scores 8MB/s writes and 24MB/s reads.
Conclusions
The Sony Microvault USB Flash Drive for Smartphone is a very useful flash drive particularly if you want to use it with smartphones and tablets.
Pros:
- Small and compact size
- Cap has attached strap
- Micro USB OTG connector for smartphones and tablets
Cons:
- Included file manager app does not support Android 4.4