Smartphones get hacked for all manner of reasons; acquiring sensitive files, emails, pictures and videos, spying on users and even as a means of blackmail.
There are a number of ways a phone can be hacked and a bevvy of programs out there that make mobile espionage even easier. So how do you find out whether you're phones been compromised and what can you do to prevent it?
How to spot signs of hacking
Evidence that suggests that a smartphone might be being monitored, spied on or is bugged in some way is often, unsurprisingly, well hidden. Despite the advancements in today's spyware, however, there are still steps you can take that could help diagnose the presence of a virus or evidence of hacking on your phone.
A sudden drop in battery life
When a phone is tapped, it records chosen activities and transfers them to third-parties. What's more, even in standby mode, your phone could be used as a listening device to capture conversations nearby. These processes result in increased power consumption, which means your phone's battery drains faster than normal by a noticeable amount.
If you can, see how your battery life compares with those using the same model of phone or better yet, if you have a phone with a removable battery, try inserting it into another device of the same model/type and see whether longevity is any different. If you notice a discernible difference, there's a chance that your device is either defective or being tapped.
Battery heat build-up
If your phone feels warm despite you not using it much, (or it having been left in the sun - don't do that either) this could be an indication of background processes or data transference taking place, without your knowledge. Notable increases in battery temperature as a result of such actions can be used to indicate such behaviour.
Activity without input
When not being used, your phone should be completely silent (save for calls, incoming notifications and alarms you've set). If your phone makes unexpected noise, the display suddenly lights up or it restarts for no reason, then someone could be controlling your device remotely.
Unusual text messages
Spyware may send secret and/or encoded text messages to your smartphone. If such programs don't work as their creators' intended, there's a chance you might spot such messages. Texts like these will likely include nonsensical combinations of numbers, symbols and characters. If this happens regularly, your phone might under the effects of some form of mobile spyware.
Increased data consumption
Less-sophisticated spy programs may cause data consumption to skyrocket, as they pass information off of your device. Accordingly, you should pay close attention to whether your monthly data usage increases dramatically for no reason. Good spy programs, however, require very little data or can spread data packet usage out, making them much harder to identify in this manner.
Noise during phone calls
If you hear clicking, unusual background noise, the voice of the other party sounds far away or is only transmitted in fragments during phone calls, someone may be eavesdropping. Since telephone signals are transmitted digitally these days, such unusual noises are far less likely to be attributed to 'bad signal' especially if you know you usually have strong connectivity in the area you're making your calls.
Long shutdown process
Before switching off your phone, all running processes must end. If data is being transmitted from your smartphone to third-parties, these illicit actions also have to be completed before your device can switch off.
If switching your phone off takes longer than usual, especially after a call, after sending emails or text messages, or after surfing the Internet, this could mean that such information has just been transferred to someone.
How to identify spyware on Android or iOS
With Android devices, spy programs can often be identified by the presence of certain files or folders on your phone. It may sound obvious but if filenames contain terms such as "spy", "monitor" or "stealth", this may be an indication that spyware is (or has been) present.
If you actually find evidence of such files, it makes sense to have your device checked by a specialist. Simply deleting or removing these files without knowing exactly what they are or how to safely remove them is not recommended.
With regards to iPhones, it's a lot harder to search through your device's directories for unsavoury files. Thankfully, there are other ways to remove spyware from an iPhone; like making sure both your apps and iOS itself are up to date.
You can check for app updates on the App Store and check that your iPhone is running the latest build of iOS by going to Settings > General > Software Update'. Performing these actions should remove any unwelcome files or profiles on your device. Before doing so, back up all important data stored on the phone.
If nothing else is working and you're sure you Android or iOS device has been compromised, you can always perform a factory reset - provided that, again, all your important data, including photos, contacts and files are backed up beforehand.
How to reduce the risk of being hacked
If you haven't already, it's advisable to set up a screen lock of some sort (even a simple six-digit PIN or password is better than nothing) to prevent unauthorised access to your device in future.
For Android devices, there are even apps, such as App Notifier, that notify you by email when a program is installed on your phone and warn you when someone wants to perform unwanted activities on your device.
Nowadays, there are also a wealth of security apps from reputable developers that offer phones (and the data stored on them) effective protection against hackers.
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