Using smartphone apps vs proper EMF metres—is there actually a difference?

I've seen loads of ghost hunters using those cheap EMF apps on their mobiles (the ones that cost 99p), and I'm wondering whether they're actually detecting anything real or if it's all just picking up phone signals and general interference.

I've got a proper Mel-Meter that cost me about £120, and the readings are wildly different from what my smartphone app shows. The Mel-Meter seems way more sensitive and selective, but I want to know if I'm just throwing money away or if there's genuine scientific difference.

Has anyone done a proper side-by-side comparison? I'm thinking of doing some tests in my flat (which might be haunted, still investigating) and I want to use the right equipment.

Phone apps are rubbish, mate. They're measuring ambient electromagnetic radiation broadly, but they're not calibrated and they're affected by your phone's own electronics. A proper EMF detector uses shielded circuits and specific frequency ranges. You're not wasting money on a Mel-Meter - you're getting an actual instrument instead of a novelty app. Big difference.

The thing about EMF readings is that elevated readings don't necessarily mean ghosts. Faulty wiring, electrical substations, power lines, mobile masts - all of these create EMF spikes that get picked up. You need multiple detection methods working together (thermal imaging, digital recorders, accelerometers) to rule out mundane causes first. EMF alone is basically useless.

which might be haunted, still investigating

Out of curiosity, what's making you think it's haunted? Sounds, apparitions, cold spots? Asking because most "haunted" properties are actually just poorly insulated, have damp problems, or are near electrical infrastructure. The readings might tell you something interesting without proving paranormal activity.

I've tested both extensively. Phone apps pick up basically everything - they're omnidirectional and unshielded. The Mel-Meter is narrower in range but much more accurate for specific frequencies. If you're serious about this, get the Mel-Meter and also invest in a decent thermal camera (the FLIR One is about £200 and decent). Do sweeps of baseline readings before you assume anything unusual.

Have you considered just having an electrician check your flat? Honestly, 90% of people who think they're haunted just have electrical problems. Not trying to be rude, but that's usually the answer. Once you've ruled out the boring stuff, then you can get excited about the proper ghost hunting kit.