SPECIAL MENTION: Forgetting your keys at the office can ruin your ride home. So Tile, the maker of tiny trackers that can slip into wallets and hang off keychains, came up with Smart Alerts—notifications that warn you should you leave a designated place (e.g. home or the gym) without a needed possession. With over 14 million Smart Alerts sent, the feature is the most popular aspect of Tile’s premium subscription, which costs $2.99 a month. —Patrick Lucas Austin
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