The first generation Tile ($25) has been my preferred Bluetooth Low Energy tracker for a while now. Its main drawback, however, is its thickness. At 5.3 millimeters, it can make wallets bulge.\n\n\nThe new, 2.4-millimeter\u00a0Tile Slim ($30) solves the fat wallet problem. You can also adhere the skinny tracker to a laptop, tablet or other possession using optional stickers ($5 for three).\n\n\nI like Tile Slim a lot, but it's not going to completely replace what's now called Tile Original, at least not for me. Here are two reasons why.\n\n1. Tile Slim isn't keychain compatible\n\nThe original Tile has a hole that lets you easily add the tracker to a keychain. Tile Slim lacks a keychain hole. That's because the new tracker is designed to complement, not compete with, Tile Original. And in order to create a device as thin as Tile Slim, it was necessary to remove the hole, according to a company spokesperson.\n\n2. Tile Slim's ringtone is quieter\n\nThe ringtone that Tile Original emits when you tap the device's "Find" button in the Tile app is relatively loud, at 90 decibels, according to the company. The louder the tracker's sound, the easier it is to find a missing item.\u00a0In comparison, Tile Slim's ringtone volume is 82 decibels. When you place the original and Slim trackers next to each other, you can hear the difference.\u00a0A Tile spokesperson explained that the slimmer form factor didn't allow for as much of an amplified sound as Tile Original.\n\n\nSpeaking of ringtones, Tile Slim has four of them, including a "Blues for Slim" tone that's kind of cool. The original Tile has only one ringtone.\n\n Tile\nTile competitors\n\nTrackR bravo ($30) is probably Tile's closest competitor, but even though its ringtone is rated "up to 85 decibels," the audio level is noticeably quieter than the original Tile and a bit softer than Tile Slim.\u00a0Also, I prefer Tile's mobile app to TrackR\u2019s.\n\n\nOther similar trackers that I haven't tested include Duet and Lapa ($30 each). As with Tile and TrackR bravo, you can get a discounted price if you buy Duet and Lapa in quantity.\n\nTile's ambitions\n\nAlong with the introduction of Tile Slim, the company announced the new\u00a0Tile Smart Location Platform, which lets other companies integrate Tile's Bluetooth tracking technology into their products. Partners currently include Nomad, which plans to offer a portable, trackable power pack ($90), and EcoReco, which is developing a trackable scooter.\n\nTile Slim vs. Tile Original\n\nTile Original is best suited for use when thickness isn't a big concern, such as with keychains, backpacks and suitcases. The higher ringtone volume may help you locate an AWOL item. Otherwise, for wallets or for attaching to devices, Tile Slim is the way to go.