I've given up, been in review for way to long. They say it's 'technical issues' but that's gone on for weeks. Scam in my opinion
Can you give us the date that you submitted it and the date they changed the status to "In Review"?
In my experience, it has taken anywhere from a day to a month from when I submit to when they approve (or reject). Depends on the time of year. In December, they receive a lot of submissions and simultaneously, a lot of employees take time off. So December is always a bad month to submit during.
Also, "In Review" is a misleading status. Submissions are reviewed separately by two individuals. You get told its "In Review" from the moment the first person starts reviewing your app until the second person finishes. Each person reviews your submission for anywhere from a few minutes to a few hours, but there's an indeterminate period of time, possibly over a week long, between when the first person finishes and the second person starts.
It'd be nice if they broke down "In Review" to "In First Review", "Awaiting Second Review", and "In Second Review".