final --> for primitives --> value can't change. for non-primitives --> you can't change the reference and point it to another object. Note : It is different from immutability.
Hands down, the Bluetooth speaker with the longest battery life is the Fugoo. It offers up to 40 hours of battery life, nearly twice the battery life of other leading Bluetooth speakers in this category. Given how long its battery lasts, you might even forget that the Fugoo needs to be plugged in to charge.
The Good The Sony SRS-X3 is elegantly designed mini Bluetooth speaker that delivers strong sound for its small size. It has a built-in speakerphone capabilities, NFC tap-to-pair technology for smartphones that support it, and reasonably good 7-hour battery life.ts design is straightforward and elegant and the speaker itself has a nice, smooth-to-the-touch finish. It comes in a few different colors, including black, red, and the white model I tested. Alas, no protective carrying case is included, but Sony does sell one for $20.