yimmi :
I currently own a nexus 5 i have no issues so far but i consider the upgrade to a more powerful phone as future proof,I am thinking of one plus 2 but because of the invite system I am thinking of zenfone 2 ,just to say I kinda prefer vanilla experience but any alternatives-budget friendly would be welcomed(no samsungs btw)
Stick with the Nexus 5 for now, it is an amazing phone, upgrade in another year, I have one and don't plan on upgrading until I start to see a lot of lag which I haven't at all in two years, my Dad's LG G3 lags way more and it is barely a year old. Wait for the next batch of high powered smartphones with even more powerful specifications.