I'm not sure that the Germans had technological superiority before or during WWII. They had some areas of technological superiority but they also had some deficits. On the ground their tanks at the beginning of the war were at a rough parity to most of what the Allies had in the field and throughout the war they often faced equal Allied tanks--especially against the Soviets. German artillery was horse-drawn for the most part, which is hardly technologically superior. In the air their fighter force was highlighted by the -109, which was a late 1930's fighter well into its development cycle and was excellent for the time. However, the French and British weren't totally outclassed in the air--especially the British. The German bomber force lagged behind the British and Americans throughout the war. At sea the German u-boat force was good but not nearly dominant and their surface fleet made no real difference in the war. If you're referring to innovations like the V-2 and the Me-262, the V-2 was a failure as a weapon of war (it killed as many of its workers as it killed Allied civilians) and the Me-262 was not a huge improvement over the British and American jets at the time.
The Nazi military wasn't technologically superior to the Allies. Their successes early in the war were due to doctrinal innovations and strategic gambles that paid off in the short term but doomed the regime in the long run.
Do you have a specific item in mind that the Germans held superiority that we could discuss in more concrete terms rather than generalities?
German technology was hardly superior to the Allies. The situation was more that both sides spent their limited resources in the development of different technologies. Germany was prone to over-engineering new designs, and slow, problematic births of experimental new prototypes that, while impressive as propaganda and terror weapons, in the end had little strategic effect.
The Allies developed models and designs that were mobile, easily produced and repaired, dependable, and easy to operate. The Germans often developed models that, while more complex, struggled in all these areas. In an equal battle one-on-one between a freshly built M4 Sherman, and a Tiger or Panther for instance, the Germans enjoyed considerable technological superiority. But the German was more likely to have broken down on the way to the battle, or to have struggled to move itself quickly into the battlefield, or it may just be outnumbered and out produced across the theatre as a whole. The Allies considered these factors when designing their equipment. The Germans didn’t, or were unrealistic about what they though they could achieve.
In regards to technological innovation, both sides made considerable progress, but the leaders of the innovational technologies had a very different approach to the practical applicability of their inventions. The Allies saw a specific problem and designed a piece of technology to counter that specific problem. The Germans fantasised and built amazing prototypes that had little practical use, and largely existed in a vacuum, failing to take into consideration how it would operate in conjunction with the rest of the military and industrial machines.
The V2s for instance were an incredible idea, but they failed to take into consideration how to defend their launch pads from conventional allied aircraft, which was a fatal flaw in their use as a weapon on the battlefield. They were useless in the defence of France, which was the conflict where weapons were actually needed. They therefore failed to contribute to the war effort. Their designers operated independently, and failed to take into consideration what the military needed in order to win. The rockets caused a lot of damage to Britain, but at this stage of the war, it contributed nothing to defeating the enemy they actually faced, who was landing beach-heads on their coast. Britain had already shown that it could weather indiscriminate civilian bombing, and the V2, in the end, was just more of the same. It was, in the end, an expensive toy. Similarly, the jet aircraft was an incredible machine, but Germany didn’t need a handful of expensive, irreplaceable, gas-guzzling planes at this point. They needed thousands of planes in order to take back the skies. The ME-262 could never have done this on its own. It wasn’t the weapon they needed at the time.
In comparison, the British developed the RDF, (later called RADAR) in response to a specific practical need. It was this that won the Battle of Britain. They developed Bletchley and the first computer in response to the specific need to crack enigma, and it was this that won the crypto war. The Allies developed the Atom bomb, while Germany had barely got its own atomic program off the ground. In many cases, Britain aimed its technological skills at specific problems and won important strategic victories, while Germany largely hamstrung itself by squandering its technological prowess in independent fantasies that had no impact on the war.
Personally, I place the early German successes in WWII at the feet of General Hans von Seekt, who made preparations during the 1920's. He reorganized the Army, and developed their new tactics.
When AH came to power, Gen von Seekt was moved aside, since the good general was a firm anti-socialist. vonSeekt always planned to destroy Poland, but warned against attacking Russia or France.
It was von Seekt that developed the relationships that resulted in Germany having a forbidden tank testing facility in Kazan Russia (to keep these developments away from the eyes of the allied inspectors). Germany could spring their new tank designs and tactics on Poland, and ironically...the "stupid" Russians used the facility to develop the T-34, much to Hitlers dismay
By the end of the war (in spite of Hitlers bungling) the German army had night vision, and the Italian battleship "Roma" was sunk by a single German guided missile (Fritz-X)