Unless you're an early adopter who cycles smartphones every six months, you've undoubtedly felt it -- a loss of performance in your current device. And this isn't an Android vs. iPhone issue. Users on both sides often complain that their phones just aren't as fast as they once were.

Rest assured: it isn't all in your head. At least, not completely. It's quite possible that your device has actually slowed down, and there are several potential causes. In this post, we'll cover these reasons and what you can do about them.

Note that we're talking about long-term performance losses after owning a device for a year or longer. Short-term slowdowns, such as those caused by memory leaks, are often fixable with a simple reboot.

1. OS Upgrades

When you first bought your device, it came with a specific version of its operating system. Maybe Android 4.4 KitKat, maybe iOS 7, both of which released in 2013. When those OS versions came out, they were developed with a certain set of hardware specs in mind.

Fast-forward to today and overall hardware specs have drastically improved. Features are added to both Android and iOS, and these improvements are made with the newer hardware specs in mind. As such, newer versions of an OS require more computing power and resources for a smooth experience.

In other words: if you have a 2013-era device that came with Android 4.4 KitKat and upgraded it to Android 7.0 Nougat, you simply don't have enough juice to handle all of the extra overhead. Hence, the device feels slower.

What can you do about it? Not much, unfortunately. Feel free to apply minor upgrades (e.g. from Android 7.0 to 7.1) but avoid major upgrades (e.g. from Android 7.1 to 8.0). Keep your device in the era it came with, and upgrade the device itself if you want to take advantage of a newer OS version.

2. App Updates

While all types of software can succumb to something called "feature creep" -- the continued adding of new-yet-arguably-unnecessary features -- mobile apps are some of the worst offenders. Even so-called "lightweight" apps can quickly grow bloated over time.

But the real tragedy is that most developers aren't mindful of the resources used by their apps. In fact, as overall device hardware improves, developers tend to get lazier as far as resource management goes. Over time, apps tend to eat up more RAM and CPU but your hardware stays the same, so performance feels slower.

Take an app like Spotify and compare how it is now to what it was like back in 2014. The 2014 version would run perfectly fine on today's phones, but today's version of Spotify would likely sputter on a 2014-era phone. Apply this to all apps on your device and it's easy to see why it may seem slower now.

What can you do about it? As apps grow bloated, you can replace them with lighter-weight alternatives. Likely offenders include note-taking apps, media apps, social network apps, and office apps. In some cases, an older version of an app might be available. So long as it doesn't have any glaring security issues, it might suit your device better than the latest version.

3. Background Apps

Another reason why your phone feels slower is that you have more apps installed now than when you first got the device. If you don't believe me, go to your phone's settings and look at all of your downloaded apps. Most people think they've only installed 10 or so apps, but are often surprised to see closer to 40 or 50.

The problem is that some apps run in the background although you aren't actively using them. For example, email apps are always checking for new incoming emails, messaging apps are always awaiting new messages, note-taking apps are always syncing, etc. Even animated live wallpapers and home screen widgets need resources to do what they do.

Every additional app in the background uses CPU and RAM, which leaves less CPU and RAM for the apps you're actively using. This can impact performance and is one reason why task killer apps are so bad.

What can you do about it? Identify which apps are draining battery as heavy battery use tends to indicate heavy background processing. Switch to a static wallpaper and avoid relying on widgets. Uninstall apps you don't use. Disable background processing in apps that allow it.

4. Memory Degradation

All smartphones and tablets run on flash memory, which is a type of solid-state storage medium with no moving parts. The most common type of flash memory is called NAND. While NAND is fast and affordable, it does have a few quirks that can impact performance.

First, NAND memory grows slower as it fills up. The exact mechanisms behind this are beyond the scope of this article, but suffice it to say that NAND memory needs a certain amount of "empty blocks" to operate at peak data-writing performance. The speed loss with full storage can be significant.

Second, NAND memory degrades with use. There are three kinds of NAND memory -- SLC, MLC, TLC -- but they all have write cycle limits per memory cell. When the limit is reached, the cells wear out and impact performance. And since your device is always writing data, deterioration is unavoidable.

Note that TLC is a type of NAND memory pioneered by Samsung. It's the cheapest to produce but has the worst durability: 4,000 write cycles per cell versus 10,000 in the more standard MLC type. This might be why Samsung devices have a reputation for slowing down more than non-Samsung devices.

What can you do about it? We recommend staying under 75 percent of your device's total storage capacity. If your internal storage is 8 GB, don't cross the 6 GB threshold. This can also help extend the life of cells through a technique called "wear leveling," thus delaying performance degradation.

5. Greater Expectations

In spite of all the above, your device might simply feel slower because you perceive it to be slower, not because it has actually slowed down.

There's an interesting phenomenon where search traffic for "phone slow" spikes after new phone releases and big OS updates. Nobody knows for sure what this means, but one interpretation is that when something new comes out, what you have right now suddenly seems worse.

Furthermore, as the people around you upgrade their devices, and as you acquire other devices in your household (e.g. a brand new laptop), your baseline for good performance goes up. Your Galaxy S3 Mini may have been "amazing" at one point, but now that your standards and expectations have risen, it's now "a piece of junk."

What can you do about it? Learn to accept it or upgrade your device. Android users could flash a new, light-weight ROM.

How to Speed Up a Slow Mobile Device

If your device is slower than you'd like, and you're sure it isn't all psychological, then there are a few things you can try.

For Android users: We have a guide on what works and what doesn't work when it comes to speeding up Android performance. Effective tactics include cleaning up the home screen and rebooting on a regular basis. Don't forget to free up storage space, too. As a last resort, reset back to factory state.

For iPhone users: Not as many options as with Android, but you can try manually clearing RAM, avoiding battery-draining apps, and freeing up storage space. As a last resort, reset back to factory state.

Was this post helpful? Have you experienced a slowdown with your own device? Are there any tips or tricks that have worked for you? Share with us in a comment down below!

Image Credit: Dean Drobot via Shutterstock.com