7 apps to find holiday deals

For Slice, the big business day is neither Black Friday nor Cyber Monday, but what it calls "Tracking Tuesday." The free app culls your email for purchases, organizes them for quick review, and tracks your orders. Using shipping numbers, Slice follows your purchases and sends you a notice when an item is at your doorstep.

"Most people will wonder, 'is it going to get there on time?' We can tell you, in real time, every day, where every package is and when it gets delivered," Slice CEO Scott Brady says of his holiday shipping approach.

One new feature this year: Slice will notify you if the price of an item you bought has gone down -- which in some cases means you can get the difference back.

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