I will recommend you Oppo F7. It comes with a superior processor with a good amount of RAM assuring that the device can run buttery smooth even while multitasking. It draws its required energy from a 3,400mAh Li-ion battery which might be sufficient for a day.
For the selfie lovers, the smartphone offers an impressive 25MP front camera.
You can also check the complete comparison here: Oppo F7 vs Vivo V9 vs Huawei P20 Lite vs Asus Zenfone 5 (8GB, 1.6GHz)