Samsung: T-Mobile + Orange
I was in Wal-Mart ? years ago; the salesman said a simple Samsung cell phone [no contract, using T-Mobile] would work with T-Mobile & Orange; as I remember T-Mobile, a German co., owns Orange. The salesman spoke the truth!
* The phone was US $90., w some 'free' minutes. It worked fine with both; Orange unlocked it later - 500 P; it takes 10 - 15 seconds to switch & manipulate the 2 chips.
* 3- 4 years now; it usually works perfectly. Not expensive; I buy few minutes monthly. But, . . I don't use the phone much.
* Palm cell phones normally can do the same; but, Palm phones, usually PDAs are prohibitively expensive [my opinion].