Been digging into crypto arbitrage scanners lately and honestly there's way more options now than I expected. The whole idea is pretty straightforward - you find price gaps for the same coin across different exchanges and capitalize on that spread before the market corrects. Some of these tools are actually wild with what they can do. ArbitrageScanner seems to be the heavyweight here, covering like 75 plus centralized exchanges and 25 decentralized ones. What caught my attention is they're scanning across 10 different blockchain networks, so you're not just looking at exchange-to-exchange plays but also cross-chain opportunities. That's where the bigger margins can hide. Their screener lets you set custom thresholds and they'll ping you when something matches. Pricing runs from $69 to $795 monthly depending on what tier you grab. Then there's Cryptohopper which takes the AI angle - it's more of a general trading bot but handles arbitrage pretty well. You connect it to your exchange accounts via API and it monitors for opportunities automatically. They charge around $29 to $129 monthly. If you want something cheaper to start, Bitsgap is solid at $26 for the base plan, and Coinrule has this free forever starter tier which is honestly generous - 2 live rules and some template strategies with no time limit. TradeSanta and 3Commas are also in the mix, both offering multiple bot types beyond just arbitrage. The mobile access is becoming standard now, everyone's got iOS and Android covered. One thing worth noting though - a crypto arbitrage scanner is only as good as the liquidity you're working with. Major coins on top exchanges, sure, you'll find consistent spreads. But smaller cap stuff? Forget it. The fees and slippage will eat any profit you might've made. Also these tools vary wildly in how they work - some are full platforms, some are just notification services, some are exchange-native bots. Really depends if you want a complete trading suite or just alerts when something's worth your attention. Honestly the free trials are your friend here, test drive a few before committing to a subscription.