I like the visual style of this game! Especially the magnet effect and charging for the explosion are really cool and adds lot to the value of the game. If the game still would have some explosion like visual effect when the enemies die it would be perfect!
Speaking of the explosion, it was really interesting mechanic that the nearby enemies get destroyed when enough collectables are acquired. It added an option for the player to take risks by getting close to an enemy horde to kill more enemies at once.
Otherwise the game was fun play at the beginning but it became repetitive after a while. The game mechanics or the enemies did not change and there was no difficulty curve to add tension. Maybe you could consider possibilities to add variety to the game as I believe it would really make the overall experience a lot better!
The magnetism theme is used but in the end it does not effect the gameplay a lot. It feels good as a player that the collectables fly in my direction when I get close but it somehow feels more like a increased usability feature or cool extra effect rather than a central part of the gameplay or mechanics. Might just be my opinion though.