Due to fact that there is no iPhone 5S iOS 8.2 jailbreak release available and with Apple Watch launch today many owners of jailbroken devices should make a decision whether to keep device jailbroken, or lose jailbreak to pair iPhone with Apple Watch.
As this complicated question worries thousands of jailbreakers we will think how to keep jailbreak on the mobile device and use Apple Watch.
Many jailbroken devices owners use their devices in their day-to-day job responsibilities and don't want to lose jailbreak for using the Apple Watch.
Here are few options that you could do in this situation.
The first option is to jailbreak iPhone 6 Plus, update to iOS 8.3 and use iPhone 5S as daily driver. This step will allow to keep iPhone 6 Plus jailbroken on iOS 8.1.2, and it let use Apple Watch with iPhone 5s. So you can place iPhone 6 Plus SIM card in iPhone 5S. Then you can use iPhone 5S as daily driver, and leave the 6 Plus for jailbreak at home. It would be really uncomfortable to get used to the iPhone 5S’ screen, but hopefully a jailbreak isn’t too far off in the distant future.
The second option is to keep iPhone 6 Plus jailbroken, and use as daily driver. Carry around the iPhone 5S as well for the Apple Watch. This option is almost the same as the first option, except for the fact that you would retain the 6 Plus as daily driver, and you'd bring the iPhone 5S just for pairing and communicating with my Apple Watch. Picking this option means that you have to walk around with two iPhones instead of one.
The third option is to downgrade iOS 8.3 and pair with Apple Watch. Use iPod touch 5th-gen, which is for example on iOS 8.1, for jailbreak stuff.
This is the best option as you will enjoy full-sized 6 Plus with the Apple Watch. As iPhone 6 Plus speed is amazing it will guarantee the best Apple Watch experience. Till the time when iPhone 5S iOS 8.2 jailbreak release will be available you can use the device in day-to-day job. You would have to carry two devices.
So if you have few iOS devices available then you can choose one of this options.