Here's how Apple's iPhone design could change - if the US Department of Justice wins its antitrust lawsuit against the tech giant

The US Department of Justice, alongside 16 state and district attorneys, announced Thursday that they are suing Apple — saying the company's sleek devices and software constitute a monopoly that's price-gouging its own customers.

At the core of the suit is the charge that Apple has designed everything from its App Store to iMessage to hem in consumers, locking them into a walled garden where it's harder to comparison shop for both hardware and digital services.

One example from the suit's allegations is that Apple has made it harder for rival payment apps, like PayPal or Stripe, to work on iPhone, prioritizing Apple Pay.

Fortunately, for most average people sitting on the sidelines, Apple's past legal battles with the European Union (EU) provide excellent foreshadowing of what big changes might be coming to the iPhone, if the US government emerges victorious.  

Apple users might even find themselves saving some money over time.

The US Department of Justice said Thursday they are suing Apple, calling the company's sleek devices and software a monopoly. California's Attorney General Rob Bonta (above) was one of over a dozen state attorneys announcing an antitrust case against Apple alongside the DOJ

Fortunately, for most average people sitting on the sidelines, Apple's past legal battles with the European Union (EU) provide excellent foreshadowing of what big changes might be coming to the iPhone, if the US government emerges victorious 

Software options beyond App Store 

Thanks to the EU's Digital Markets Act, Apple users on the other side of the Atlantic have the opportunity to choose a different default digital marketplace to buy and download software for their phone. 

In truth, Apple's potentially monopolistic use of its App Store impacted app developers as much as Apple hardware owners: the tech giant took a 30-percent cut of all of app-and-subscription costs via the captive marketplace.

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The move left many app makers no choice but to pass that cost increase on to the owners of Apple iPhones and iPads, at least, as the DOJ now contends.

Here's how the Cupertino-based company explained its adjustments made to comply with the new EU regulations: 'Users are able to manage their preferred default app marketplace through a new default setting for app marketplace apps. Platform features for finding and using apps like Spotlight are integrated with a user's default app marketplace.'

But customers should be advised that Apple has opted not to enforce any of its own rigorous standards on these other app store alternatives, possibly leaving them something of a 'wild west' atmosphere.

Alternate browsers to Apple's Safari 

The EU determined that Apple's setting of its own browser, Safari, on all Apple iPhone and iPad devices constituted a monopolistic practice.

So, now, while Safari remains pre-installed, a European user's first experience opening the app leads off with a prompt offering them the chance to download and install a different web browser as their primary option. 

While Safari remains pre-installed in the EU, a European user's first experience opening the app leads off with a prompt offering them the chance to download and install a different web browser as their primary option

As part of their support page complying with the EU regulations, however, Apple noted that browsers and browser apps are a main portal by which scammers and other malicious actors attempt to gain access to people's digital life. 

So, unlike the App Store situation, 'Apple will only authorize developers to implement alternative browser engines after meeting specific criteria and committing to a number of ongoing privacy and security requirements.'

Those included, they said, mandating that all third-party browser and browser-app makers produce 'timely security updates to address emerging threats and vulnerabilities,' if they want in on iPhones or iPads.

Wider compatibility for payments via iPhone

Up until now, Apple has restricted the ability of users to enjoy their device's Near Field Communication (NFC) technology between only other Apple devices or established payment terminals used by retailers.

That's made it less convenient to, for example, pay back a friend who uses Android, via the simple and handy nearby tapping that NFC is known for.

Now, Apple has introduced an option that allows an iPhone owner to permit their other banking or wallet apps the ability to employ host card emulation (HCE), which  widens the scope of what apps on their phone are compatible with NFC terminals or mobile devices that accept contactless payments.

'To help protect user privacy and security on iPhone, developers who want to build HCE payment capabilities into their banking or wallet app,' Apple said, 'need to apply for the HCE Payments Entitlement.'

The application process, they said, will ensure all these so-called fintech apps 'meet certain industry and regulatory requirements, and commit to ongoing security and privacy standards.'

US Attorney General Merrick Garland (front) and Deputy Attorney General Lisa Monaco, announcing the antitrust lawsuit against Apple in Washington, DC, on March 21

Apple boss Tim Cook

iMessage - an end to green text bubbles? 

The European Union ultimately left iMessage — and its habit of treating messages from other phones like second-class citizens — alone.

The EU found that only 10 percent of residents even used iMessage, preferring WhatsApp among other options, making monopolistic concerns somewhat moot. 

But the DOJ can't make that same case: a whopping 85 percent of American teenagers use iMessage, for example, according to Fast Company, and Apple itself has recognized the control its texting app holds in private.  

'The #1 most difficult [reason] to leave the Apple universe app is iMessage,' the business site said, quoting the writings of a former Apple employee. 'iMessage amounts to serious lock-in.'

Although the issues at play are technical, iMessage monopoly is more than just green vs. blue text balloons: communications between iMessage users enjoy less compression of images and video, and most importantly come with Apple's best encryption and privacy protections.

Both of these key value-adds are denied to texters from other phones contacting an iPhone user in their life. 

A DOJ victory could widen the network of important individuals you can connect with safely on your device, but Apple is not conceding the issue without a fight.

'We believe this lawsuit is wrong on the facts and the law,' Apple said in a statement. 'And we will vigorously defend against it,'