[Device Reviews and Information] Alberto96:
Introduction

This is the CUBOT Rainbow 2.

Hardware

Similar to the previous Rainbow (1) from CUBOT (that i had to refuse due to customs issues, dammit), this one features the same CPU and RAM, but with more ROM and a better overall Camera Hardware. It is powered by a Mediatek MT6580 SOC clocked at 1.30GHz, a bit outdated and slower compared to the MT6737 used in almost all low-end devices nowadays, together with 1GB of RAM and 16GB of ROM. Also, there are two rear-cameras, used to handle the Blur effect. (even though i'm not sure about its real utility)

Unboxing

Packaging comes with some accessories: 1x Micro-USB Cable, 1x 5V/1A USB Charger, 1x Quick Start Guide, 1x Compliance Regulation Booklet, 1x Anti-Shock TPU Cover and the Smartphone (of course). A plastic screen protector is pre-applied.

Talking about the dimensions, the device is pretty compact is comfortable to handle. It is 14.4x8.84x0.88cm, with medium bezels, and weights 157g, maybe a bit heavy for a plastic 5 inches device.

The device looks stylish, with a matte back cover that, ignoring the fact that is a fingerprint magnet, it looks really nice, similar to the old Galaxy S1 from Samsung. There are no Metal Parts, everything is made of plastic.

On the front side there is the usual 2.5D Curved Display and the upper front side of the device features a Front-Facing Camera with a Big Flashlight, an Earpiece, and the Sensors hole that includes Light, Proximity and Gesture Sensors. A Notification LED is here, supporting only one color: Blue.

Here you can see the LED in action.

On the lower front side there is the classic soft-keys zone, with Recents, Home and Back button. Not backlit. You can notice the hidden microphone somewhere between the home and back buttons.

On the back side there is the removable back cover, but the battery isn't removable. The upper rear side of the device features the Dual Camera Sensor supported by a Single-LED Flashlight.

On the lower rear side there is only the Model Name with some Certification Logos. The speaker is positioned on the lower side of the device.

Device

Screen

Unlike some other 5 inches devices i have reviewed, this one features an interesting screen with accurate color reproduction, nice viewing angles and no strange banding issues.

The Light Sensor supports smooth light changes, with a proper auto-brightness management. This is its maximum brightness. Excellent Brightness.

Viewing Angles matches IPS screen capabilities.

Camera

This device features a GalaxyCore 8MP Rear Camera together with a GalaxyCore 0.3MP Secondary Rear Camera, offering some nice shots, but do not expect to see something outstanding. This is still a budget device, don't forget it.

A nice amount of details is here, low-light shots are decent and the level of noise isn't really high.

"HDR off" on the left and "HDR on" on the right. Some improvements are noticeable.

Macros are not great at all, unlike Wide photos. Auto-Focus management needs to be improved.

The Single-LED Flashlight doesn't seem to be powerful for dark shots, but it is acceptable.

SLR/Blur Photos seem OK, i'm not an expert with this kind of photos so i don't know if this is a good result or not.

As regards Video Recording, 1080p videos are surprisingly great, much better than most budget devices i have reviewed. Smooth and with an high level of details.

Front Camera records sufficient photos for video-chat and occasional shots. Also, it seems to be a Wide-Angle variant, and the extra flashlight seem to help a bit. On the right you can see the same photo taken using the front flashlight.

Audio

Speaker's Quality is decent, a low amount of low-frequencies is here and the volume is decent. I don't understand why the second speaker grill hasn't been used at all, considering that the microphone is on the front side.

As regards the Microphone, it works decently well in any case (in-call, VOIP, etc...), and the earpiece is loud enough to be used in any condition.

GPS

Unfortunately the GPS isn't the best part of this device, the signal isn't really high and indoors it costantly loses the signal. For a plastic device, running on a stable MT6580 chipset, this is a bit disappointing.

Indoors on the left, outdoors on the right.

Telephony, Mobile Network & WiFi

This device doesn't support 4G networks, so you have to use your old 3G HSPA+ (42MBps max) connection to use your Mobile Data plan.

Signal Reception is accurate, but 3G coverage is just perfect here where i live so that's something i would have expected. Just like what happens with other devices, 3G Network Speed is low, thanks to my crappy Mobile Network that has lower than average 3G performance.

WiFi 5GHz isn't supported here. With my 2.4GHz network, i was able to reach almost 23mbps, connected at 65mbps, this seems to be the slowest WiFi performance i have ever seen. CUBOT, please take a look at this issue.

Battery Life

As always, i have measured the real battery capacity using my USB Tester, and it seems that the real battery capacity is slightly higher compared to the declared value (declared 2350mAh, real ~2440mAh).

This is the PCMark Work 2.0 Battery Benchmark, the battery runtime is great considering the battery capacity.

As regards battery charging times, the 5V/1A charger doesn't allow any super fast charging, but in just a bit more of 2 hours it gets charged completely.

Software

Following all previous CUBOT devices, also this one comes with a completely clean Android OS, and most important, based on Nougat 7.0. Something rare to find with MT6580 devices, such an old chipset with such a new Android Version, something that i would have never expected from Mediatek. There are some apps that i might recommend you to disable (screenshot attached), in order to get the best performance.

All Mediatek features are still there such as Gestures, Scheduled Power On/Off, etc…

No Malwares Detected using MalwareBytes Anti-Malware.

Even though the device isn't so powerful, it is still able to handle basic tasks, but do not expect to run multiple apps in the same time, some micro-lags are here with some latency issues.​