You collect sports gear by playing as any character except the special character.

You can BUY extra balls from the play store for gold coins..

I was wondering this too since I only saw this yesterday and to complete my daily tasks I need to collect another 130 of them and I already collected 120.. But now they dont show up in any levels.

You can collect pops by completing daily tasks which lets you overcome some difficult situations, sometimes that would be the only way if the company itself dont send you some cheats. So someone else can not tell you how to complete these levels as that kind of non random game play is not available. And different types of pops can be used in a situation. Like you can use 3 different kinds of pops to get rid of the bricks some of which only go a very short distance like the rock pops..

Many of the levels need cheats issued by the company itself. Sometimes I have been stuck on a level for a few days but then they give me a cheat that lets me overcome the level. Now of level 765..