Arado Ar.196 - German users, part one

The first A-0 versions were delivered to the Kriegsmarine between November and December 1938 and were armed with a single defensive MG.15 placed in the rear, while the similar B-0 versions were issued to the shore-based squadrons.
Those were followed in June 1939 by the A-1 in order to equip the practical majority of the German surface fleet.
Soon after the war started, in November 1939 the heavier A-2 version was designed and produced. It was shore-based and included underwing shackles for two 50Kg bombs plus two 20mm FF cannons placed in the wings. It had also a single 7,92mm MG.17 machine gun placed in the cowling at the starboard side. It was replaced by the A-4 version in December 1940 which featured a reinforced airframe with an additional radio. Most of the main German surface ships had an Ar.196 as spotter airplane, among the them the famous Battleships Bismarck, Tirpitz, the Battlecruiser Scharnhorst or the Heavy Cruiser Prinz Eugen, among many others.

Sources:
1. https://en.wikipedia.org/wiki/Arado_Ar_196
2. http://www.lexikon-der-wehrmacht.de/Waffen/Ar196.htm (translated)