I have one and used it to photograph some blue tits coming and going to the nesting box on my wall to great effect. I was able to see when the birds arrived and left without disturbing them by being visible.

of stars

Ooh mono

I have no issues with my iPhone but I just tried with my wife's Galaxy and although it recognises the Flu card it is displayed as disabled in the list. Not sure why.

You shouldn't have any issues, unless the bird is flying straight at you at 90mph. But even a Canon would struggle with that!

Hi Alistair,
Not sure where you are going wrong, I sold my Siggy 70-200 OS because it was sitting on the shelf gathering dust. My DA*50-135 is the one that I used instead for my karting shots because the IQ, colour and contrast was in a different league straight out of the camera. Now forgive me but the karts probably travel a tad quicker than a 21 year old horse
Stick with it and work it, accepting its drawbacks and you will have a lens that delivers in spades.
Check out these and these on my Flickr and Llandowkartclub on Flickr, all mine, the last 6 meetings have all been taken with the 50-135 with a spattering of Siggy 70-200 and DA*300.
The 50-135 gets some bad publicity for sports and maybe the focus is a little slower but when you come away with photos of the quality, aharpness, colour and contrast this lens produces it is well worth the effort. Granted there may be a few frustratingly out of focus shots but even with the Siggy that happened and another occasional togger with his Canon 6d mounted with the legendary 100-400 admitted not every shot was nailed.
The last meeting in pouring rain (no sign of the Canon man that day) I shot using two bodies for the first time, I had the DA*300 on my K-5iis and the DA*50-135 on my K-3. I'm pretty sure the K-3 nailed way more shots and seemed to drive the DA*50-135 much faster or more accurately that the 5iis used to.

Please bear in mind the photos are a record for the kids not an art gallery.

Cheers C.
got it

Where's the link? I can only find it for $39.99

One went on eBay very recently and sold for £520, you may get some interest if it was closer to that kind of price.

As above, the feet and breast plumage don't yet have the adult colours so probably a juvenile getting seen off by the old man.