I applied 3 weeks ago. I have been married 15 months so I covered the period from marriage until application.
5 months of Skype screenshots- not every conversation but enough to show we were regularly using it.
Then, my ticket and photographs from visiting my husband.
And then just 11 months of whatsapp call logs. I do regret not including screenshots of whatsapp conversations! There were just too many to cover for 11 months..but I've heard the more the better...
In addition I included screenshots from Facebook messages from random times throughout the 15 months and the bit on our timeline that says 'now married to..'
Fingers crossed!