I’ve used Instashare for some time to send screenshots when testing on both iOS and Android devices. The fact it works on both iOS and Android platforms means its better than anything built into those systems.
You can also download and install Instashare apps on your Mac and PC, which I use as the location to send the screenshots to.
To share screenshots/images, you normally open up the Instashare app and then select the image(s) to share and the device to send to – pretty simple and quick.
Now in iOS 8, there’s an Instashare extension – this means you don’t even have to open up the Instashare app on the device – in the Camera Roll, select Share icon and then you can directly select Instashare (alongside the usual Mail, Message, Twitter etc) and then select the device to send it to. See screenshot below.