Your question raises an important issue. How critical is it if the app is not available on iPhone, but rather as a desktop version on your Mac or Windows PC? The problem is that Apple has removed many essential backbone features needed for WiFi apps to function properly on iPhones and iPads, creating a significant disparity between iOS and macOS eco-systems. While there certainly are some WiFi analyzers for iPhone and iPad, you will either need to purchase an expensive hardware that would work with apps like WiFiman or Ekahau, or settle for the "average precision level" of apps like NetSpot (a big name in the category of WiFi survey and planning apps for non-experts, and in fact some experts, too). Essentially, you must choose between spending up to $15k for Ekahau, which may even require attending several webinars and taking a dedicated certification course to master all of their technicalities, or $15 for NetSpot. For a use case like yours, the choice is obvious IMO.
On the other hand, what I suggest is using a Mac or Windows laptop and opting for a desktop version of those WiFi survey & heat map generating apps, still minding the price point, of course.
However, if you insist on doing this with your iPhone (or iPad) and don’t feel like spending $1k-15k, then NetSpot for iOS might be your only option for a quick and clear WiFi survey. You can find it here.
BTW, NetSpot for Android is also a decent solution, and in fact, offers more features not being restricted by Apple’s crippled APIs for third-party devs.
But here are some thoughts on solving your network stability issues without the need for specific apps:
1. Router Placement: The location of your router significantly affects signal strength. Place the router in a central location, ideally on the same floor where you use WiFi the most. Avoid placing it near metal objects and appliances that emit electromagnetic waves, such as microwaves, refrigerators, and TVs. If your apartment has multiple levels, try positioning the router in the vertical center of your space. Again, generating a WiFi heatmap to see how your coverage changes with different router placements may help a lot (kudos, NetSpot).
2. Reduce Interference: Other electronic devices can interfere with your WiFi signal. Try to minimize interference by keeping the router away from cordless phones, Bluetooth devices, baby monitors, and microwaves (sorry for repeating myself). Also, consider the impact of thick walls and floors made of materials like concrete, which can drastically decrease your WiFi signal.
3. Change WiFi Channel: Most routers are set to automatically select a WiFi channel, but this channel may be crowded with signals from your neighbors’ WiFi networks. Log into your router’s settings via a web browser using the router’s IP address. Check the channel settings and manually switch to a less congested channel, typically 1, 6, or 11 on 2.4 GHz or any channel on 5 GHz if your device supports it. WiFi Inspector mode is free in NetSpot, and does exactly that. WiFi Explorer is also a decent alternative, but a bit busier in terms of UI.
4. Add Repeaters or Extenders: If changing the location and channel doesn’t solve the problem, consider using WiFi repeaters or extenders to boost the signal in hard-to-reach areas. These devices can help extend the range of your WiFi network by repeating the signal.
5. Upgrade Your Hardware: If your router is older, it might be lagging behind in sustaining high-speed wireless connection throughout a multi-floor apartment. Consider upgrading to a newer router that supports the latest WiFi standards (like WiFi 6E, or WiFi 7). Mesh WiFi systems are also a great solution for multi-floor homes as they provide seamless coverage over a large area.
