A heavy leather conditioner should be done 3-4 times a year, more in hot climates. I like to use saddle conditioner, but I am surrounded by farm supply stores. Think of Armor All as just a cheap cleaner/greaser (not degreaser), apply as desired.
Like Hazmat says, absolutely no Armor-all anywhere in or on your car. That shit is horrible for your ride. I've had friends in the autobody, detailing, and car sales businesses urge me to avoid that stuff at all costs.
Armor All isn't the end of the world. It's good for use in large quantities, like working out a pop, grease, or wax stain. It'll keep the leather protected for short term between full conditionings. Just don't let it build up and collect dust. I recommend a LIGHT degreasing (like a damp cloth soaked in dish soap and water or vinegar and water and squeezed) of the leather between Armor All and the real conditioner.