It's really difficult to recommend something without any set budget. Really the Macintosh is a nice platform to work on, and if you're developing iOS apps there's no question about it, you need a Mac.
I personally don't hate Apple, but their laptops are overpriced a tad. However the build quality is still amazing and they have excellent customer support. Personally, I would look at a baseline 13 inch MacBook Air or Pro. You're not going to be doing demanding programming on this, however I would recommend picking up 8GB of RAM as you ARE going to notice the difference when using multiple applications (especially Java, which is extremely RAM/CPU hungry)
The air comes to $1,300 with the 1.8GHz Dual Core i5, 8GB RAM, 128GB SSD.
Another Windows laptop that you should look at is this ultrabook:
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This is excellent for the money. It's better than the Air by far.