Miben más az Android 4.4 mint a 4.2?

Először is nézzük meg mi az új 4.3-ban:

Bluetooth low energy support.[112]

Bluetooth Audio/Video Remote Control Profile (AVRCP) 1.3 support

OpenGL ES 3.0 support, allowing for improved game graphics[112]

Restricted access mode for new user profiles[112]

Filesystem write performance improvement by running fstrim command while device is idle[113]

Dial pad auto-complete in the Phone application[112]

Improvements to Photo Sphere[114]

Reworked camera UI, previously introduced on Google Play edition phones[115]

Addition of "App Ops", a fine-grained application permissions control system (hidden by default)[116]

4K resolution support[117]

Many security enhancements, performance enhancements, and bug fixes[118]

System-level support for geofencing and Wi-Fi scanning APIs

Background Wi-Fi location still runs even when Wi-Fi is turned off

Developer logging and analyzing enhancements

Added support for five more languages

Improved digital rights management (DRM) APIs

Right-to-left (RTL) languages now supported[112]

Clock in the status bar disappears if clock is selected as lockscreen widget

És ehhez még jön a 4.4 újításai:

Refreshed interface with white elements instead of blue

Ability for applications to trigger translucency in the navigation and status bars[127]

Ability for applications to use "immersive mode" to keep the navigation and status bars hidden while maintaining user interaction[128]

Action overflow menu buttons are always visible, even on devices with a hardware "Menu" key, which was officially deprecated by Android 4.0[129]

Optimizations for performance on devices with lower specifications, including zRAM support and "low RAM" device API[121]

Wireless printing capability[121]

NFC host card emulation, enabling a device to replace smart cards[121]

WebViews now based on Chromium engine (feature parity with Chrome for Android 30)

Expanded functionality for notification listener services[121]

Public API for developing and managing text messaging clients[130]

New framework for UI transitions

Storage access framework for retrieving content and documents from other sources

Sensor batching, step detector and counter APIs[121]

Settings application now makes it possible to select default text messaging and home (launcher) application

Audio tunneling, audio monitoring and loudness enhancer[131]

Built-in screen recording feature (primarily for developers, as usage of ADB is required)[132]

Native infrared blaster API

Expanded accessibility APIs and system-level closed captioning settings

New experimental runtime virtual machine, ART (not enabled by default)[133]

Bluetooth Message Access Profile (MAP) support[134]

Disabled access to battery statistics by third-party applications[135]

Settings application no longer uses a multi-pane layout on devices with larger screens

Wi-Fi and mobile data activity (TX/RX) indicators are moved to quick settings[136]

Applications' access to secondary storage (memory cards on devices with internal primary storage) is restricted to their designated private directories only, while full access to internal primary storage is still allowed[137]

Itt találod a változások listáját:

[link]

Természetesen megéri frissíteni.

Mindig megéri frissíteni, hisz teljesítménynövekedést hoznak a frissítések, és új funkciókat.

Az más kérdés, hogy az OEM-ek (Samsung meg ilyenek) lehet elrontanak pár dolgot, és nem ritkán előfordul, hogy instabil lesz a rendszer, hamar lemeríti az aksit, stb. Illetve előfordulhat, hogy nem minden funkció lesz elérhető, tehát amit olvasol, hogy mit tud a 4.4, az mindig csak Nexus készülékekre 100% igaz, illetve azokra jön 100% megbízható frissítés, ami minden téren jobb lesz, mint a régi, nem-Nexus készülékeknél a gyártón is múlik, hogy meg tudja-e jól csinálni a készülékére.