On Friday, reports surfaced about three of America's biggest retailers that detailed each was making further headway into the ultra-competitive online delivery space.

Amazon.com AMZN

Just weeks after the e-commerce giant finalized its acquisition of organic grocer Whole Foods, Amazon has announced a new partnership with Olo, a New York-based food delivery service. The up-and-coming delivery option provides digital order and pay technology to 200 restaurants like Applebee's, Chipotle CMG , Denny's DENN , Shake Shack SHAK , and Wingstop WING .

As part of the deal with, Olo's clients would be listed on the Amazon Restaurants section of Amazon.com; Olo will then provide the tech that published menus and take orders while Amazon arranges deliveries. Amazon Restaurants has also implemented Rails , which is an Olo product that allows restaurants to take delivery orders from Amazon and other third-party services.

Not only will this partnership help Olo's customers connect with Amazon Restaurant's delivery services, but it will also give Amazon's customers access to more restaurant options.

Shares of food delivery leader GrubHub GRUB has taken a beating on the news, falling as much as 7% before regaining some ground; the stock is currently down about 3.3%.

Walmart WMT

In a blog post , big box leader Walmart announced that it is testing a service that delivers groceries to your home, and unloads them for you straight to your refrigerator-even when you're not home.

Working with smart-lock startup August Home and same-day delivery service Deliv, Walmart customers can order groceries and other items online, and orders will then be securely brought in to their homes when ready. When the delivery person rings a customer's doorbell, it triggers a smartphone notification, which you can then watch the delivery take place if you choose.

Delivery associates enter a customer's home by pressing a one-time, pre-authorized passcode into the smart lock; the worker would then carry groceries to the kitchen and unload them in the fridge, while any other items would be left by the front door.

Walmart said the test will take place in Silicon Valley, with a small number of August Home users that have chosen to use the service. It is not clear how long this current test will last, or how this aspect of Walmart's delivery program will evolve.

Target TGT

Fellow big box frontrunner Target recently upped its delivery service game, with Target Restock offering city dwellers next-day delivery on everyday essentials ordered online.

After testing the service over the summer, the company expanded Target Restock to eight additional cities, which makes it available to over 70 million people. It's now available in Atlanta, Chicago, Los Angeles, New York, Philadelphia, San Francisco (coming mid-October), St. Louis, and the Washington, D.C./Baltimore, MD areas.

Similar to Amazon's Prime Pantry, customers can fill a box (up to 45 pounds) with typical household items-think laundry detergent and cleaning supplies-for a flat $4.99 fee; Amazon charges $5.99 per box. Another advantage: Target doesn't charge an annual membership fee, and is available to any online Target shopper in the supported metropolitan regions.

This is just one of the many new initiatives Target is trying out, and many seem to be hitting their mark; the company's smaller format stores and in-house brands were a big reason for its better-than-expected results last quarter. And, Target Restock's expansion is a sign that shoppers are consciously choosing Target over other online options for things like paper towels and other grocery-related items.

Perhaps Amazon's dominance is not as all-encompassing as it appears.

Interested in the other top stories of the week? Listen to Zacks Friday Finish Line to catch up on the week's financial and investment news.

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Amazon.com, Inc. (AMZN): Free Stock Analysis Report

GrubHub Inc. (GRUB): Free Stock Analysis Report

Wal-Mart Stores, Inc. (WMT): Free Stock Analysis Report

Target Corporation (TGT): Free Stock Analysis Report

Chipotle Mexican Grill, Inc. (CMG): Free Stock Analysis Report

Denny's Corporation (DENN): Free Stock Analysis Report

Shake Shack, Inc. (SHAK): Free Stock Analysis Report

Wingstop Inc. (WING): Free Stock Analysis Report

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The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.

The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.