Then Germany and parts of Poland would now be a smoldering crater of a nuclear death zone with little chance to ever clean it up in this or any of the next generations.
By no later than 1944, the German Luftwaffe was in no position to conduct any offensive action anymore. The air superiority of the allied was total. Including Germany. So even if he had the bomb, he certainly would not have any means to deliver it anywhere beyond the areas that Germany still occupied.
Given his "strategy" (I'll use that term loosely here) of scorched earth, it's likely that he would have had it used to increase the destruction on the retreat, to decrease the useful materials the approaching allies could use (as he did) but also to create a zone of denial that they would either have to avoid (and thus lengthen the supply lines) or cross while accepting the losses (something the Soviets would probably even have done).
In short, Germany having the bomb after 1944 would maybe have lengthened the war (though this is unlikely due to the Allies having it in Summer 1945 and Berlin having actually been the original main target, Germany was just lucky that it surrendered before the bomb was ready for shipment). It would certainly have meant more suffering for Germany due to self inflicted nuclear destruction (Hitler himself considered the Germans "unworthy" at the end of the war because they have "proven to be the weaker people and not worthy of continued existence". Together with his fantasy of a "Götterdämmerung", an epic apocalypse that has to happen to "his" Germany if he himself fails, it's likely that he would have called for the destruction of large cities before they fall into enemy hands. What would have been interesting is to see how many people would actually have been fanatical enough to do it).
