Can you view another person’s call log over the internet without having their phone? Are there legitimate online tools that really do this? Were they simple to use, or did they require additional information to work?
You generally can’t check someone’s call history online without having access to their phone.
Most call logs are private data stored by the phone itself or the mobile carrier. Without the device, the account credentials, or explicit permission from the owner, there is no legitimate online service that can pull someone’s call history for you.
Btw, is it related to kids monitoring or anything related to employee drama? 
There is no legitimate way to see someone’s call history unless that person explicitly gives you that information. There is no website where you can enter their number and access their call logs. You can access call logs in these situations.
Your own account: If you are the account holder (for example, a parent or business owner), some carriers let you view basic call records (numbers and timestamps) through their official portal.
With the phone and permission: Accessing call history directly on the device or through a linked cloud account (like Google or iCloud) when credentials are shared.
Parental or employee monitoring: Only when installed on the device with clear consent and in compliance with local laws.
I totally agree with you @TechRider. I wanted to add my two cents regarding parental monitoring as you mentioned.
I use Xnspy, and the app does everything from call recordings to call log history, with timestamps, phone numbers, and contact names. Been using the app for the last 6 months, and I haven’t faced any major problems.
The app works in stealth mode, without appearing in the notification center or the home screen. Easy installation and hassle-free setup. If you are looking to monitor SIM logs, then it might be for you.
On iOS, the most practical options are using Family Sharing with Screen Time (which shows call and message summaries) or accessing the device’s iCloud backup, but only if you have the Apple ID and password, or viewing it with a tool like iBackupBot to check call history.
Otherwise, you would need to set up a parental monitoring app, Xnspy, just like @RenderInventive mentioned, on the phone in advance.
Ah, welcome to the land of Android tricks 
. Compared to iOS and its tightly controlled ecosystem, Android is far more open, which means you have a lot more room to work with, with no Apple-style restrictions holding you back.
A few Android-specific pointers worth knowing:
If you have access to the person’s Google account (often the case with family-managed devices), some call data can sync through Google services.
Other than that, monitoring apps like Xnspy can sync call logs quietly once they are installed. You usually only need brief physical access to set things up, and after that, everything can be viewed online.
As a side perk, Android Device Manager tied to a Google account can sometimes give you insight into general device activity. It won’t show full call details, but it can still be useful in a pinch.
Android’s flexibility definitely makes this kind of oversight much easier than on iPhones.