mobile phones' consumers diferenses
20
27
23
23
21
20
20
23
26
22
20
23
21
21
21
21
24
20
21
26
19
22
24
20
22
21
21
23
18
21
19
20
23
23
22
22
20
23
20
21
19
23
21
20
21
22
20
24
22
19
20
21
21
21
20
21
20
21
23
20
21
21
19
19
21
29
19
23
22
22
18
29
21
19
22
20
20
20
20
21
21
24
20
19
19
23
19
21
20
20
21
20
20
22
21
21
23
19
19
24