Germany was way ahead with some weaponry - they developed the world's first jet fighter (the ME 262), the world's first proper assault rifle (Sturmgweher, on which the AK47 was based), the world's first military rockets (the V2 - on which the Apollo was based), the Tiger tank was more than a match for almost anything the Allies could throw at it, the 88mm gun was one of the most versatile and effective pieces of artillery made (as a field piece, in anti-aircraft role, anti-tank). The Allies couldn't wait to snap up Nazi scientists in order to get access to all that invaluable knowledge - one of the reasons they were in a race with the Russians. The Germans were apparently only a few months off completing the atomic bomb by the time they surrendered.

They were also ahead with tactics - the Blitzkreig, use of paratroopers (think Eben Emael), etc., etc., In Poland they were faced with cavalry charges (against tanks) and after Dunkirk the British realised this was not going to be like World War One. Their navy was inferior - especially in size - to Britain's and this was their main weakness from an armaments point of view. but had they managed to sucessfully invade England the Royal Family would have capitualted and the navy would have had to surrender anyway.