LR 5 can't connect with LR Mobile. You need LR CC 2015 which is subscription based, monthly fee.
I have only just took out the £10.10p per month subscription today and this is the version it came with?
Ok then you must be running a 32bit OS. What exact operating system are you using?
I just checked LR 5.7.1 and it does have the option to connect to LR Mobile in the Preferences.
Have you Signed in and Joined?
I never used LR Mobile with LR 5 and only recently started using it at all with LR CC 2015. So I'm not that familiar with it.
I have signed in and joined, I think I am using a 32 bit system as the photoshop cc that downloaded has (32 bit) written at end of file name. I think it's windows 7 that I'm using. should I have received lr cc with my subscription??
If you are running the 32bit version of Windows 7 the newer 64bit versions of LR and PS won't run on it. LR 5 was the last version of LR to run on 32bit OS's.
Yes with your subscription you are entitled to the newest version of LR, LR CC 2015.9, but since it can't run on a 32bit OS then the only version you can install is LR 5.
Open Control Panel and click on the System icon to check the bit version.
You can always upgrade to a 64bit OS. that is if the CPU you are running can run a 64bit OS. But even a Core 2 Duo is a 64bit CPU which came out about 10 years ago.