"What's in store?" means "What's going to happen in the future?" rather than "What is being kept back?" Sometimes there is an implication that the things "in store" are planned by someone, but not always.
Edit: I forgot about "Stick to my tune." That is a piece of poetic writing which takes advantage of being part of a song. "Stick to" here means "keep to" or "stay with" in a metaphorical sense; the lyricist is saying that he should carry on doing what he normally does (his "tune" in this metaphor). It's more commonly found in phrases like "Stick to your guns".
Here's the quote with a bit more context:
"We're going to double down on
secrecy on products," Cook said, but on
other things, "we will be the most
transparent company in the world," -
like social good and supplier practices.
Double down is originally a blackjack term to play for double or nothing.
It is used more generally to mean make a calculated gamble to double your commitment, to concentrate or focus on something.
But it seems like use is changing, and it's simply means you will try twice as hard (as there's always some inherent risk in everything).
Cook is simply saying Apple are going to be more serious and committed about product secrecy.
The linked question asks about:
Palin
is notorious for doubling-down on
perceived missteps, typically blaming a biased media for not
telling the whole story.
This is similar; Sarah Palin concentrates and pays extra attention when people claim she makes mistakes, usually trying to deflect blame to the media.
Best Answer
Merriam Webster Last intransitive/transitive verb
So make it last means make it continue for a long time (long being subjective as bridges are built to last for a hundred years or more while clothes are made to last for maybe ten years)
In the song he wants the feeling of being with his girlfriend to last, to continue to have that feeling for a long time.
You can use it in many situations