The real question here is how much you are willing to spend. Once you give a figure, it will be easier for us to give recommendations. In fact, you may not even need to buy an old used phone.
I am planning to buy a new mobile phone, I am a fan of Sony music.
I was wondering if its a good choice to buy Sony Xperia Z3+ Dual now as in March 2017.
Will the phone be fast with new applications? or Will it lag with new Applications?

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