Or what our company does - merely provides a subsidy to buy a device. Just like covering running costs. (Employee chooses, buys and owns the device. The subsidy is enough to buy an android - if want an iPhone or other high-end phone, you just pay the extra money.)
The question I have is what the smartphone is used for. If it's to receive and make phone calls the employee could simply give a SIM and a basic phone. I've seen 20 euro GSM and 50 euro UMTS phones, with a lot o extra features like camera, fm radio, mp3 player, web browsing and so on.
Even a low end Android phne costs under 100 euro, and makes possible to VPN or ssh easily in a remote system, and anyway some 'dumb' phones are capable of this.
On the other hand if specific smart features of a phone have to be used for work-related operations, having to support a generice device is a IT support nightmare.
If you make anthrax illegal, only criminals will have anthrax!
Why make illegal trash speed metal bands CD and tapes? Especially when not banndin One Direction...
Without life, Biology itself would be impossible.