Employee phones and tablets now hold the same sensitive company data as laptops, yet they are not always protected to the same standard. This leaves a clear opening for attackers, particularly as phishing increasingly targets employees through text messages. According to the Cyber Security Breaches Survey 2025/26, 43% of UK organisations experienced a cyber security breach or attack in the last 12 months, with phishing behind most incidents.
Securing your mobile estate does not mean replacing every device or rebuilding your security stack. It starts with five practical steps:
1. Decide your BYOD stance.
2. Enforce it with mobile device management.
3. Add mobile threat detection.
4. Consolidate your strategy.
5. Prepare for when a device is lost or stolen.
Together, these steps help you balance security, compliance and user experience, whether you manage a handful of devices or an enterprise-scale mobile workforce. The aim is not simply to secure the hardware. It is to protect the data, identities and applications your employees use every day.
Below we outline how to implement each step and build a mobile security framework that's resilient against modern threats.
1. Decide your BYOD stance and put it in writing
Start by deciding whether staff can use personal devices for work and under what conditions. The National Cyber Security Centre (NCSC) defines bring your own device (BYOD) as employees using personally owned devices for work, with the organisation owning the corporate data on that device while the hardware itself stays the employee's property.
That split is where the risk sits. You cannot fully control a device you do not own, but you are still accountable for the data on it under UK GDPR.
Awareness of this is growing, but slowly. According to the cyber security breaches survey 2025/2026 report 64% of UK micro businesses now restrict access to company-owned devices only, up from 58% the year before, yet VPN use for remote access still sits at just 36%. That gap is exactly where an unclear policy causes problems.
The NCSC sets out five steps that hold up well in practice:
- Work out your objectives, user needs and risks.
- Write a clear policy.
- Understand the extra costs involved.
- Choe your deployment model.
- Only then implement the technical controls.
Agree on the policy and the "why" first, and the technology choices become straightforward. Skip straight to the technology and you'll end up bolting a policy on afterwards to justify decisions you've already made. Lock BYOD down too hard and your staff will simply go around it with unmanaged personal apps and accounts that give you no visibility at all.
2.Enforce mobile device management (MDM)
A policy is only useful if you can enforce it. Mobile device management (MDM) gives your IT team centralised control over provisioning, app management and remote lock or wipe across every device in the fleet, whether you manage ten devices or several hundred.
We've covered how MDM works in more detail, including deployment models and how it supports compliance with Cyber Essentials, ISO 27001 and UK GDPR, in our guide to what mobile device management is and why it matters. It’s worth reading alongside this piece if you are building the case for MDM internally. Our Mobile Device Management solution applies that same control across your device estate and is designed to support mixed company-owned and BYOD fleets, rather than forcing one ownership model on every device.
3. Add mobile threat protection to catch what MDM misses
MDM controls the device. It doesn't stop a user tapping a convincing smishing link, installing a malicious app from outside an official store or connecting to a rogue WiFi hotspot in a coffee shop. That is where mobile threat protection, sometimes called mobile threat defence, comes in. It actively scans for phishing attempts, malicious or misconfigured apps, network-based attacks and compromised or jailbroken devices, and can isolate a device the moment something looks wrong.
The distinction matters because MDM and mobile threat protection are often confused. Organisations may assume MDM protects against phishing and malware, but it does not. Our Mobile Threat Defence service works alongside MDM to close that gap.
4. Consolidate your strategy
Steps one to three do not work as separate projects. They work as one system, and that is where enterprise mobility management (EMM) comes in. EMM brings device management, app management, identity and threat protection into a single strategy. Done well, it means a lost phone, a phishing attempt and an unauthorised app are all visible from the same place, with consistent policy applied whether someone is on a laptop in the office or a phone on the train.
For Microsoft 365 organisations specifically, this usually means Microsoft Intune for device and app policy, paired with Microsoft Defender for the threat protection layer. We've written about how to put this into practice in our guide to how businesses can use Microsoft Intune to protect their endpoints. The same thinking extends beyond mobile. Our Microsoft Defender for Business and Endpoint Detection and Response services carry the same protection across every device type, with 24/7 monitoring behind it, for organisations that want one consistent policy rather than one per device.
5. Prepare for when a device is lost, stolen or compromised
However good the policy, devices can still go missing or become compromised. Test remote lock and wipe before you need them, then check them regularly to make sure they still work as expected.
This is also where mobile security stops being a purely technical question and becomes a compliance one. Under UK GDPR, a lost device holding personal data can be a reportable incident. Being able to show an auditor exactly what controls were in place, and that they worked, is what a Cyber Essentials or ISO 27001 assessment checks. Build that evidence trail before you need it, not after a device goes missing.
Your mobile security checklist at a glance
| Component | What it protects against | Where we can help |
|
1. BYOD policy |
Unclear ownership of data and devices, inconsistent rules across the business |
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2. Mobile device management |
Unmanaged devices, lost or stolen hardware, uncontrolled app installs |
|
|
3. Mobile threat protection |
Smishing, malicious apps, rogue Wi-Fi, compromised devices |
|
|
4. Enterprise mobility management |
Disconnected tools and inconsistent policy across devices |
|
|
5. Lost/stolen devices & compliance evidence |
Reportable GDPR incidents, failing to demonstrate Cyber Essentials or ISO 27001 controls |
Protect every device. Reduce every risk.
Employee mobile devices can no longer be treated as an afterthought in your security strategy. They should be protected to the same standard as laptops and other endpoints. Start by deciding your BYOD stance, enforce it with MDM, add mobile threat protection, bring the controls together and prepare for when a device goes missing. Treat these as five connected steps, rather than separate projects, and you can reduce one of the clearest gaps in your security.
Start by seeing how your current mobile estate measures up. Get in touch with our business mobiles and security team, or call us on 0333 234 0011, to talk through BYOD policy, MDM or mobile threat protection needs.
Take our free interactive assessment to review your current mobile security, identify potential:
https://www.wavenet.co.uk/business-mobiles-iot/mobile-security-assessment
FAQs
What's the fastest way to start securing employee mobile devices?
Start with the policy, not the tools. Decide which devices employees can use for work, what data they can access, and what happens if a device is lost, stolen or compromised. Once that is clear, you can enforce the rules with mobile device management and add mobile threat protection where you need it.
What's the difference between BYOD security and mobile device management?
BYOD security is the policy layer: the rules that decide what employees can do on personally owned devices and what data they can access. Mobile device management (MDM) is the technology that enforces that policy, provisioning devices, controlling app installs, and enabling remote lock or wipe. You need the policy decided before the technology can enforce it properly.
Is BYOD safe for UK businesses, and what does the NCSC recommend?
BYOD can be safe with the right controls, but it isn't safe by default. The NCSC recommends starting with your objectives, user needs and risks, then building a clear policy, understanding the costs, choosing a deployment model, and only then implementing technical controls such as MDM and mobile threat protection.
What is mobile threat protection, and do I need it as well as MDM?
Mobile threat protection, also known as mobile threat defence, detects phishing, malicious apps, network-based attacks and compromised devices that MDM alone cannot identify. MDM manages and controls the device, while mobile threat protection detects attacks against it. Most organisations need both working together.
How does mobile device security fit into wider endpoint security?
Mobile device security is part of endpoint security, which protects every device connected to your systems, including laptops, desktops, phones and tablets. Enterprise mobility management brings device management, app management, identity and mobile threat protection together for mobile devices. Endpoint detection and response extends monitoring and threat response across your wider device estate.
How does Wavenet help UK organisations secure employee mobile devices?
We combine Mobile Device Management and Mobile Threat Defence with Microsoft Intune and Defender expertise, so BYOD policy, device management and mobile threat protection work as one system rather than separate tools. Get in touch or call 0333 234 0011 to see how your current mobile estate measures up.
