This is a bit of a mixed bag for me.
Some good things:
There is great presentation here without doubt. The music is quite pleasant but if there is anything lacking, it would be that there is not as much sound FX as I would have liked. From the ants, to ants picking up food. The lack of feedback makes it a bit confusing and detracts the experience a bit.
Biggest caveat:
The lack of a clear or understandable game loop. I don't think the game loop is very clearly defined or strongly communicated to the player. There is a vague 'timing your ant workers' but there is not enough feedback to keep me engaged.
In other games where player input is relatively limited to sending units, such as 'The Battle Cats' on the Apple Store, there is still some strategy involved in matching units you send to units the enemy sends with changing dynamics. Whereas in this game, there is no clear, or demanding strategy on the onset. We are only trying to get soldiers to the other side, with no clear 'conflict' with an enemy player, and deaths that occur seem to occur from an environment/external player not involved in the battle at all.
My opinion is of that the design should be revisited to an extent. For example, maybe add an element of combat where ants actively repel the spider (but never able to kill it), with soldier ants in the background constantly supplying food to keep soldier ants fed and capable to fight.