Not having done forex, my guess is that *most* of the time, the major currencies would drift within a few percentage points of each other week to week, so sticking with 0.99 would work better than 1.02 one day, 1.01 the next, then 0.98. 1 is psychological cut-off, going above that reduces sales.
If it was that simple, I'd be a Forex millionaire by now, as would many others, since buying each dip would be a viable strategy. Unfortunately (or fortunately, since I didn't go broke), I ultimately threw out about 6 months of development into a complex algorithmic trading system that targeted Forex. Bear in mind I did that as somebody that's not afraid to take risks; unfortunately, currency pairs swing wildly, even when no geopolitical events can be easily attributed to the fluctuations.
To get an idea, take a look at the 52-week pictures for a few currency pairs:
USD/EUR
GBP/USD
GBP/EUR
These are major currency pairs, and as you can see, they move wildly on a daily basis, let alone weekly or monthly. Sometimes there are obvious events such as Brexit, but most of the time it's due to innumerable factors and a dash of irrationality. Fixed currency conversion rates do not have a place in modern society, and are almost always a scam. What Apple is doing is wrong, and I'm sure at least some of the people involved know.
actually it's the only way to be fully protected against local root (kernel/system daemons) vulnerabilities, keyloggers, data theft, etc.
I'm not entirely sure about the scope of what you're claiming here, but know that virtual machine escapes aren't uncommon. I'm not saying that virtualizing the browser is a bad idea (defense in depth and all that), but it won't get you perfect security. Also, in some cases, it's possible to attack the host OS without leaving the VM. Then there's the sensitive information within the VM (user credentials, session cookies, etc.), which doesn't require an escape.
Always leave room to add an explanation if it doesn't work out.