Stepping past the least costly A1, the 1.0 TFSI, and spending more for a 1.4 TFSI Sport gets you climate control air conditioning (which maintains a set temperature), and front seats with extra side support for brisk cornering. You also get the Audi Drive Select system, which lets you adjust how immediately or lazily the car responds to your pressure on the accelerator pedal (you can choose Comfort, Efficiency or Dynamic). Wheel diameter rises an inch to 16 inches, and the tyres have a lower profile (which sharpens the steering a bit).
Spending more again on a 1.8 TFSI S Line gets you very bright Xenon headlights and eye-catching (and long-lasting) LED daytime running lights. You get a better multimedia system, with a high-resolution display, integrated satellite navigation, twin memory card slots, voice control and a 20Gb hard disk for music storage. Wheel diameter rises again to 17 inches, the tyre profile shrinks further, and the suspension is firmer (for more stable handling).
In an S1, you get the very powerful 2.0-litre engine, all-wheel-drive, sport suspension that’s firmer again, and the ability to choose how firmly the car rides with the Drive Select system (via electronically adjustable dampers in the suspension).
An S1 also brings you a flat-bottom steering wheel, seats trimmed in a combination of cloth and leather, stainless steel covers for the control pedals, and a more powerful 10-speaker sound system with a sub-woofer. On the outside, various styling tweaks bring a sportier look, among them a different 17-inch wheel design.
On any A1 or the S1, a reversing camera can be ordered as an extra-cost option. Some features of the more expensive A1s can be added as options to the others (notably satellite navigation).