Options for getting picture from tablet or phone to tv

Short of buying an Apple tv (they seem to be most stable for Directvnow) found the cord at Wal-Mart to attatch from tablet or phone to HDMI then into tv. My question is how to keep device charged during use as it will drain battery fast!! Tried laptop, currently also use Roku, done multiple chats, even considering a Chromecast if it is more stable than current nightly connection issues..working on fixing that, blue square and laptop freezing for a few seconds. Done my homework on all known...

Options for getting picture from tablet or phone to tv

Using laptop for streaming DirectvNow issue

My laptop is a few yrs old, but was overkill at the time so it still runs everything great EXCEPT DirectvNow. I have it hardwired into my wireless gateway. My speeds run about 105Mbps down. Seems like every minute or so it is like I hit a pause button. Audio and video freezes for 2-3 seconds and then starts playing as normal until it happens again. Chrome is up to date, cache cleared numerous times, even did a chat and they had me reset everything in Chrome. Had 3 escalations, still occurs....

Using laptop for streaming DirectvNow issue

Comparing two routers?

I have a chance to get a high end linksys and I have a high end Netgear. If you were me would you upgrade. Yes high end is subjective. But would it be a step forward? Most internet comparisons are sponsored and I don't trust them. Two routers are:
NETGEAR - Nighthawk X6 AC3200 Tri-Band Wi-Fi Router (old)

Linksys - WRT32X AC3200 Dual-Band Wi-Fi Gaming Router with Killer Prioritization Engine (Maybe new one)

Thanks