Does my phone have a virus or is it just proboards?

Happenig to me, too.

It's likely to be a rogue ad that redirects you when it loads (so not a virus). Proboards have had some other reports of this problem, and are looking into it. To help them narrow it down, some details would be helpful:

Device and browser you are using
Time when the redirect occurred
Your location - city or area preferably

If you're able to see and make a note of what ad(s) are on the page before it opens the app store even better.

Yes please.

Mine shows a 'Message from webpage' 'Tip - "not enough memory, too much junk files, seriously affect the speed of phone!"
The only option is to click the OK button (no X available) which takes me to a store search for Dianxinos and in turn a page titled Update Android cleaning. web address is update.sztdy.com.....

and app.appsflyer.com

I'm on a Nokia Windows phone using Internet Explorer
Redirect happens repeatedly since Monday
Oxford UK

Have had this problem many times on iPad Air 2. I clear all website data and it goes away. It's a pain to reenter passwords and such but better than being redirected all the time.

It has been a while since it has happened though.

Go to Settings
on the left menu select Safari
Scroll to the bottom of the Safari menu and select Advanced
At the top of this select Website Data
At the bottom Select Remove All Website Data 
You will get a pop up with remove or cancel
select remove 

Before you do this be aware all of your usernames and passwords will need to be re entered, along with any info that might have been stored for a specific website like shopping carts.