I found an IPhone, can I use it?

I found an IPhone 4 back in April, put a lost ad of Kijiji and put signs up where I found it. 3 Months later nobody has claimed it. Can I take out the Rogers sim card, reset it, and set up a new plan with Virgin? If i do that would it be traceable?

Added (1). I live in Alberta Canada.

No. You must use reasonable steps to determine who the owner is.

The obvious step would be (since you know it has a Rogers SIM card), that the owner is Rogers. Most phones are leased. Even if not leased, it would take Rogers about 5 minutes to determine who the owner is from the SIM or serial number. Take it to the nearest Rogers outlet and give it to them. They'll know who the owner is within minutes.

If the iPhone has a Rogers SIM, chances are it is locked to their network. You would need Rogers to unlock it before it would accept another SIM. Resetting it doesn't unlock it from the network.

Yes, it would be traceable since it has a serial number which the Roger's has obviously recorded.

I wouldn't use it. First off, i've never heard of Kijiji, so maybe the owner hasn't either. Also, the iPhone may not work with your sim card, as phones are made to work with specific carriers. For example, a t-mobile iPhone will not work with a verizon sim card, and vice-versa. Finally, yes, the iPhone can still be traced even though (assuming the phone is unlocked) your sim is in the phone, not the original owners. I would just give it to the cops or apple. Wouldn't use a lost device myself.

Likely not, due to iCloud Activation Lock. Also it is locked to Rogers so it would not work with Virgin & even if it was unlocked it still wouldn't work since Virgin is a CDMA carrier & that is a GSM phone.