Size
The Akita is a little larger on average: about 45 kg (100 lb) as an adult, against 36 kg (80 lb) for the Alaskan Malamute.
Exercise
Plan for plenty of exercise with the Alaskan Malamute, and a moderate amount with the Akita.
Temperament
They differ most on loyalty (Akita: sticks close to its people; Alaskan Malamute: friendly with everyone) and on voice (Akita: quiet; Alaskan Malamute: very vocal).
Alike
Both are rated the same on independence: decides for itself.