Really depends on the type of programming you do. For many cases, any of those three will be more than enough.

If you're doing a lot of data crunching, data science, or other computation - then you'll need more CPU/GPU/etc, which takes you down the 15" route.

I opted for a 13" Macbook Pro as I travel a lot, work away from my desk a lot and generally have my computer with me anyway. If I was desk-bound I'd consider at 15", although I'd also consider an iMac/cheap laptop as an alternative combo.

I'm not a huge fan of the new Touchbar series. Actually think if Microsoft keeps it up I'll consider a Surface next round.

To add what's sure to be a minority view, I prefer the Air. But a couple of caveats. First, as a web developer my programming is not CPU intensive. Second, I have a laptop mainly so I can shuttle back and forth between home and work, and at both locations I have external displays and keyboards. That makes the laptop display (and touchbar) mostly irrelevant. Benefits of the Air are price, portability (I bike, so light weight is great), and easy connections with my Apple displays (MagSafe + Thunderbolt). Air also has better keyboard and more flexible ports)

15 inch pro. And if you are not into gaming or 3D graphics, I would not get a dedicated GPU. Might increase the lifetime of the machine a bit (less heat inside).

By the way, the iGPU is good enough for games like Hearthstone, League of Legends, etc...

15 inch pro

15 inch pro

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