Prime Day is June 23 to 26, and Lifehacker is sharing the best sales based on product reviews, comparisons, and price-tracking tools before it's over. 

• Follow our live blog to stay up to date on the best sales we find.

• Browse our editors’ picks for a curated list of our favorite sales on laptops, fitness tech, appliances, and more.

• Subscribe to our shopping newsletter, Add to Cart, for the best sales sent to your inbox.

• New to Prime Day? We have a primer on everything you need to know. Sales are accurate at the time of publication, but prices and inventory are always subject to change.

Prime Day is here, and we're all over it. As Lifehacker's Shopping Editor, I've learned many shopping tricks over the years that have helped me filter out the tricks meant to fool you into a so-called "bargain" and figure out tools to find the deals actually worth your time. Below are the 10 best tips I've got to shop smartly during Prime Day.

Download the Amazon app for app-only Lighting Deals

Many people think that what you see on the Amazon website is the same thing you would see on the Amazon app during Prime Day or a sale, but this is not the case. Amazon rewards shoppers for downloading their app by giving faster notifications and even some app-only deals. If you see a banner on the app with “Only in the App” or “Mobile Exclusive Deal,” you won't find it on the desktop site. There is also a "Watch This Deal" option in the app that notifies you in real time the moment a product goes on sale or restocks. Make sure you turn on the notifications (Settings > Notifications > Your Watched & Wishlisted Deals > On) if you want to be informed ASAP. This works great for Lightning Deals or high-demand products that you know will sell out fast.

Use Amazon's Trade-In program if you're upgrading your device

Unless you enjoy throwing away money, never throw away any tech products, no matter how old it is or its condition. Use Amazon's Trade-In program instead, which painlessly provides an offer for most tech products and all Amazon hardware. All you have to do is answer a few questions about the product and its condition, and Amazon will send you an offer through an Amazon gift card or as an instant payment toward the purchase of a new Amazon device. Sometimes Amazon will also throw in a trade-in promotional discount (often around 20%) during Prime Day.

Knowing an item's price history tells you if you're better off waiting a bit; it also ensures you're getting the best price. There are many tracking tools, but if I were to recommend one for Amazon, it's Keepa. Keepa automatically displays the price history under the image of the product. It also lets you track specific products and sends you notifications when they go below a specific price that you set. You can download the extension for Firefox, Chrome, Opera, Edge, and Safari.

Look for stackable coupons

Many Prime Day deals have additional coupon boxes on their product page—these are easy to miss, or you might assume they're automatically added to your purchase. If you see a banner with a checkbox labeled something like "Apply $20 coupon," "Save 10%," or "Apply coupon," make sure to click it and make sure it appears at checkout. You're allowed to stack as many of these coupons as you find.

Check Amazon Warehouse (or Amazon Resale) during Prime Day

We've all returned Amazon purchases. What do you think happens to all those perfectly working products you decided to return? Most of them end up on the Amazon Resale page. These products are also part of Prime Day, on top of already being discounted. These will all be open-box and returned items, but you can find things like TVs, monitors, kitchen appliances, headphones, vacuums, power tools, computer accessories, and more. And yes, Amazon checked them all out to make sure they're clean and work properly.

Take advantage of Amazon's free payment plans

Your money makes more interest sitting in a savings account (ideally a high-yield one) than giving it away to Amazon. So when they offer you a free payment plan with 0% APR and no strings attached, it's a no-brainer. Not all products will have this option, but most big-ticket items being shipped directly from Amazon do. Be careful with this, however: It's all too easy to spend more than you should. Remember: "Don't buy anything you weren't going to buy anyway."

If you made a purchase right before Prime Day, ask for a courtesy adjustment

Amazon doesn't officially price-match its own Prime Day deals, but some customer-service reps will issue a one-time credit. If they won't, you can usually return the original item and repurchase it at the sale price as long as you're still within the return window.

Sign up for our "Add to Cart" newsletter

There are over two million deals for Prime Day this year. It's extremely difficult to parse through them all and find the hidden gems. You'd need a whole team with spreadsheets working around the clock with tools and industry knowledge to bring forward the best deals available. Lucky for you, that's what my team and I do at Lifehacker. If you want everything delivered right to your inbox, sign up for our Add to Cart newsletter. We don't just cover Prime Day, either; we curate the best deals all year round so you don't miss any bargains.

Amazon is not the only retailer doing sales right now. Competitors like Walmart have the Summer Deals event, Target has Circle Deal Days, and Best Buy has Tech Fest. While Amazon has the largest volume of deals, there are always a couple of deals from each retailer that beat Amazon, so it's worth taking a look at each of them.

Check your "Buy Again" page to spot hidden discounts

Take a quick look at the products you've purchased before, if you need new versions or refills. To do this, check Accounts & Lists → Buy Again. You might even find deals specifically for you, since Amazon sometimes targets discounts to repeat buyers of household staples.

Looking for something else? Retailers like Walmart and Best Buy run Prime Day-style sales that are especially useful if you don’t have Amazon Prime.

• Walmart’s Prime Day competition sale runs from June 22-28 and includes deals up to 50% off. It’s an especially good option if you have Walmart+. 

• Best Buy’s Prime Day competition sale runs from June 22-28, and has some of the best tech sales online. It’s an especially good option if you’re a My Best Buy “Plus” or “Total” member.

• Target’s Prime Day competition sale runs from June 23-26, with deals up to 50% off. You can become a Circle member for free.