How to play

• On the rooftops of Voltopia the little bots have rolled off their charging docks. Bring every one home.
• Tap a side of the tray (or swipe towards it) to charge it. Opposites attract and likes repel: every blue minus-bot rolls towards that side and every red plus-bot rolls away from it, all at once, until a chip, the edge or another bot stops it.
• A bot that rolls onto a dock of its own sign plugs in and lights up. Each dock takes one bot.
• Two bots heading for the same cell both stop. Order matters: dock every bot in the fewest taps for three stars.
• Later: diodes you can cross only one way, and spark docks that short a bot of the wrong sign.

Features

• Endless levels, each checked by a solver: always fair, never luck, and bigger and trickier the further you go.
• Undo is always free. Free, no sign-up, works offline and installs as an app.