Asus ZenFone 4 Pro vs Asus ZenFone 2 ZE551ML
| Type | Touch | Touch |
| Dimensions | 156.90 x 75.60 x 7.60 mm | 152.50 x 77.20 x 10.90 mm |
| Weight | 175.00 g | 170.00 g |
| Display size | 5.50" | 5.50" |
| Display | Color / AMOLED 16M colors 1080 x 1920 px (5.50") 401 ppi | Color / IPS TFT 16M colors 1080 x 1920 px (5.50") 401 ppi |
| Display protection | Corning Gorilla Glass Buy screen protector
 | Corning Gorilla Glass Buy screen protector
|
| Additional display |  | |
| Protection of the secondary display | | |
| Talk time (max.) | 3G: 1650 min. (27.5 h) |  |
| Playback time (max.) | Video: 21 h (0.9 days) | nd |
| Internet browsing time (max.) | WiFi: 17 h (0.7 days) | nd |
| Standard battery | Li-Ion 3600 mAhBuy powerbank
| Li-Po 3000 mAhBuy powerbank
|
| Quick battery charging | | BoostMaster |
| Wireless battery charging | | |
| Internal memory | 64 GB, 128 GB | 16 GB, 32 GB, 64 GB, 128 GB |
| RAM memory | 6 GB | 2 GB, 4 GB |
| Memory cards |  microSD, microSDHC, microSDXC up to 2000 GBBuy memory card | microSD, microSDHC, microSDXC up to 64 GBBuy memory card |
| Operating system | Android 7.1 Nougat | Android 5.0 Lollipop |
| Interface | Zen UI 4.0 | - |
| Processor | Qualcomm Snapdragon 835 8998 | Intel Atom Z3580 |
| Processor clock | 2450 MHz | 2300 MHz |
| GPU | Adreno 540 | PowerVR G6430 @533 MHz |
| Touchscreen | | |
| SAR (10g) | 1,490 W/kg | |
| DualSIM | | |
| SIM cards standard | DualSIM(nanoSIM, nanoSIM) | DualSIM(microSIM, microSIM) |
| DualSIM mode | dual standby | Active |
| Hybrid DualSIM | nanoSIM, microSD | |
| Announced | 3Q 2017 | 1Q 2015 |
| Other names | ZS551KL; Z01GD | Z00AD; ZenFone 2 Deluxe |
| GSM frequencies | 850 900 1800 1900 | 850 900 1800 1900 |
| UMTS | 850 900 1700 1900 2100 | 850 900 1900 2100 |
| LTE standard | FDD LTE: 2600, 2100, 1900, 1800, 1700, 900, 850, 800, 700 TDD LTE: 2600, 2500, 2300, 1900 | FDD LTE: 2600, 2100, 1900, 1800, 1700, 900, 850, 800, 700 TDD LTE: 2600, 2500, 2300, 1900 |
| CDMA | | |
| Standard TD-SCDMA | 1900 2000 | |
| UMA | | |
CAMERAS - BACK
| First camera | | |
| Photo sensor model | Sony IMX362 | |
| Photo matrix | 12 Mpx | 13 Mpx |
| Resolution | | 4128x3096 px |
| Optical zoom | | |
| Flash | 2x LED | 2x LED |
| Dual-colour LED flash | | 1+1 |
| Video resolution | 3840x2160 px | |
| Video formats | H.263, H.264, MPEG4 - 30 fps | H.263, H.264, MPEG4 |
| Additional | AF, Laser AF, EIS, OIS, f/1,7 | AF, f/2.0 |
| Second camera | | |
| Photo sensor model | Sony IMX351 | nd |
| Photo matrix | 16 Mpx | nd |
| Optical zoom | 2x | nd |
| Flash | 2x LED | nd |
| Dual-colour LED flash | | nd |
| Video resolution | 3840x2160 px | nd |
| Video formats | H.263, H.264, MPEG4 - 30 fps | nd |
| Additional | FF, EIS | nd |
CAMERAS - FRONT
| First camera | | |
| Photo sensor model | Sony IMX319 | |
| Photo matrix | 8 Mpx | 5 Mpx |
| Resolution | | 2592x1944 px |
| Optical zoom | | |
| Flash | | |
| Dual-colour LED flash | | |
| Video formats | H.263, H.264, MPEG4 - 30 fps | H.263, H.264, MPEG4 |
| Additional | FF, EIS, f/1.9 | FF |
SENSORS
| Accelerometer | | |
| Proximity | | |
| Light | | |
| Magnetometer | | |
| Gyroscope | | |
| Barometer | | |
| Altimeter | | |
| Gravity | | |
| Hall-effect | | |
| Iris scanner | | |
| Fingerprint scanner | | |
| Thermometer | | |
| Hygrometer | | |
Data transfer
| xHTML | | |
| WAP | v2.0 | v2.0 |
| HSCSD | | |
| HSDPA | 42.20 Mbit/s | 42.00 Mbit/s |
| HSUPA | 5.76 Mbit/s | 5.76 Mbit/s |
| HSPA | | |
| HSPA+ | | |
| LTE DL | 603.00 Mbit/s | - |
| LTE UP | 102.00 Mbit/s | 51.00 Mbit/s |
| WIMAX+ | | |
| GPRS | | |
| EDGE | | |
| Bluetooth | v5.0 | v4.0 |
| A2DP Profile | | |
| HDMI | | |
| WiFi | v802.11 a/b/g/n/ac | v802.11 b/g/n/ac |
| WiFi frequencies | 2,4 GHz; 5 GHz | 2,4 GHz; 5 GHz |
| WiFi Direct | | |
| WiFi Display | | |
| Miracast | | |
| WiFi hotspot | | |
| IrDA | | |
| USB | v2.0 Type-C | v2.0 |
| GPS | | |
| A-GPS | | |
| GLONASS | | |
| Beidou | | |
| Galileo | | |
| NFC | | |
COMMUNICATION AND MESSAGING
| Call waiting | | |
| Conferency | | |
| Call forwarding | | |
| Push To Talk | | |
| Instant Messenger | | |
| SMS | | |
| EMS | | |
| MMS | | |
| Dictionary | T9 | XT9 |
| Swype | | |
| e-mail client | POP3, IMAP4, SMTP | POP3, IMAP4, SMTP |
| Hardware QWERTY keyboard | | |
| RSS Reader | | |
Multimedia
| Radio | z RDS | |
| MP3 | | |
| Stereo speakers | 2 | |
| Audio Jack | 3.5 mm | 3.5 mm |
| HD Voice | | |
| Sound formats | | AAC, AAC+, AMR, WAV, eAAC+ |
| Polyphony | | 64 voices |
| Video ringtone | | |
| Ring composer | | |
| Games | | |
| Java | ART | ART |
| Videophone | | |
| DVB-H television | | |
| TV-Out | | |
PIM AND ADDITIONAL FUNCTIONS
| Watch | | |
| Stopwatch | | |
| Alarm | | |
| Calculator | | |
| Currency converter | | |
| Organizer | | |
| Calendar | | |
| Flight mode | | |
| SyncML | | |
| Data and fax | | |
| Screensaver | | |
| Themes | | |
| Interchangeable covers | | |
| Voice dial | | |
| Speakerphone | | |
| Recorder | | |
| Vibrations | | |